- Double Stars -

And (32) Cep (13) CVn (4) Her (13) Mon (1) Sex (1)
Aql (9) Cet (1) Cyg (19) Hya (1) Oph (1) Tau (11)
Ari (8) CMa (1) Del (2) Leo (14) Ori (8) Tri (4)
Aur (27) Cnc (10) Dra (8) Lib (1) Peg (16) UMa (11)
Boo (8) Com (1) Equ (5) LMi (4) Per (18) UMi (1)
Cam (5) CrB (4) Eri (1) Lyn (16) Psc (7) Vir (6)
Cas (17) Crv (1) Gem (19) Lyr (8) Ser (2)

1 Ari (**)

Name: 1 Ari, STF174
Type: **
Constellation: Ari
Coordinates: 01h50m08.60s / +22°16'29.50"

Components:
m1 m2 ρ θ Year
6m3 7m2 2.9" 165° 2018
Robert Zebahl
63mm f/13.3, 46x, Bortle 6-, SQM-L 19.0
Clearly split, but tight with noticeable difference in brightness.

70mm f/5.7, 80x
At 67x pretty tight pair, but separated with a clear difference in brightness. The primary component appeared in a hint of orange. At 80x easy to separate.

8" f/6, 100x, Bortle 4, NELM 5m9+, SQM-L 21.0
Conditions in the target region: SQM-L 20.8
Nice double star with big difference in brightness.

11 Hya (**)

Name: 11 Hya, epsilon Hya
Type: **
Constellation: Hya
Coordinates: 08h46m46.51s / +06°25'07.70"

Components:
m1 m2 ρ θ Year
SP1 AB 3m5 5m0 0.2" 241° 2018
STF1273 AB-C 3m5 6m7 2.9" 309° 2017
STF1273 AB-D 3m5 12m5 18.1" 201° 2017
STF1273 AB-E 3m5 10m8 340.5" 2015
STF1273 AB-F 3m5 10m4 406.5" 265° 2015

../images/binary-star-orbits/SP1-AB-orbit.jpg ../images/binary-star-orbits/STF1273-AB-C-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6-
AB-C: Not split. Although a slight brightening was visible in the first diffraction ring, it could also have come from slight coma of the refractor.

102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3/5
AB-C: 2020-03-27: The much fainter companion is well visible as an almost round knot directly at the diffraction ring of the primary component. Very nice sight. The seeing was mediocre (3/5).
152mm f/5.9, 150x, Bortle 7, SQM-L 18.8, Seeing 3/5
AB-C: 2020-03-27: The companion is immediately visible as a tiny star close to the primary component. Due to the chromatic aberration of the achromat, there is a slight tendency to outshine. Nevertheless a nice view. The seeing was mediocre (3/5).

15 Aql (**)

Name: 15 Aql, SHJ286
Type: **
Constellation: Aql
Coordinates: 19h04m57.67s / -04°01'53.10"

Components:
m1 m2 ρ θ Year
5m5 7m0 39.4" 210° 2019
Robert Zebahl
70mm f/5.7, 22x
Striking, pretty wide, uneven pair. Primary component gleamed in shiny orange, the companion appeared slightly orange.

8" f/6, 37x, Bortle 5-, SQM-L 20.4
Conditions in the target region: SQM-L 19.9
Easy to split, evident. Both components appeared slightly orange colored.

16/17 Dra (**)

Name: 16/17 Dra
Type: **
Constellation: Dra
Coordinates: 16h36m13.72s / +52°55'27.80"

Components:
m1 m2 ρ θ Year
STFA30, 16/17 Dra AC 5m4 5m5 90.0" 193° 2017
STF2078, 17 Dra AB 5m4 6m4 3.3" 104° 2018
Robert Zebahl
55mm f/9.1, 27x
STFA30 (AC): Rather wide pair with almost equal components. C component appeared slightly yellowish-orange.

55mm f/9.1, 71x
STF2078 (AB): Grand sight!

../sketches/2019-05-18_16_17_dra.jpg

25 CVn (**)

Name: 25 CVn
Type: **
Constellation: CVn
Coordinates: 13h37m27.70s / +36°17'41.40"

Components:
m1 m2 ρ θ Year
STF1768 AB 5m0 7m0 1.7" 99° 2018
STF1768 AC 5m0 11m6 214.3" 321° 2015
KZA73 AD 5m0 13m0 335.6" 92° 2015
KZA73 AE 5m0 12m7 369.5" 139° 2015
KZA73 AF 5m0 9m4 437.3" 118° 2015

../images/binary-star-orbits/STF1768-AB-orbit.jpg

Robert Zebahl
60mm f/18.7, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 60mm. The diffraction ring of the primary component is virtually invisible. The companion appears only in few moments as an extremely faint, elongated brightening in the diffraction ring. Very difficult. Telescope should be in very good optical condition!

70mm f/16, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 70mm. Companion only visible as a subtle, elongated, not permanently visible brightening. The diffraction ring of the primary component is only visible occasionally. Difficult. Telescope should be in good optical condition!

80mm f/14, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 80mm. Companion permanently visible as elongated brightening in the diffraction ring. But the diffraction ring itself appears rather faint. Moderately difficult.

90mm f/12.5, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 90mm. Companion quite clearly recognizable as elongated brightening in diffraction ring. Relatively simple.

102mm f/11, 160x
AB: 2020-03-16: The faint companion is immediately recognizable as a distinct, slightly elongated brightening in the diffraction ring. Easy.
152mm f/5.9, 150x, Bortle 6-, SQM-L 19.1
AB: 2020-03-19: At 150x the clearly fainter companion is visible as a roundish brightening. Due to the chromatic aberration of the achromat (152mm f/5.9) the companion is almost outshined. At 180x the companion is then well, at 225x and 300x very well visible as a tiny separated star.

26 Aur (**)

Name: 26 Aur, STF753
Type: **
Constellation: Aur
Coordinates: 05h38m38.10s / +30°29'32.80"

Components:
m1 m2 ρ θ Year
AB-C 5m5 8m4 12.0" 269° 2013
Robert Zebahl
70mm f/5.7, 22x
Separable at 22x, but quite close together and pretty uneven. Primary component appeared in bright orange. At 57x easy to separate. The faint companion appeared silvery-blue.

30 Ari (**)

Name: 30 Ari
Type: **
Constellation: Ari
Coordinates: 02h37m00.52s / +24°38'50.00"

Components:
m1 m2 ρ θ Year
STFA5 AB 6m5 7m0 37.9" 275° 2018
RAO8 BC 7m0 11m0 0.6" 282° 2018
Robert Zebahl
70mm f/5.7, 22x
AB: At 22x widely separated, striking with a rather small difference in brightness. A seemed a bit warmer in color compared to B with a hint of orange. At 44x, both seemed slightly orange with very little difference in color.

41 Lyn (**)

Name: 41 Lyn, S598
Type: **
Constellation: UMa
Coordinates: 09h28m39.99s / +45°36'06.50"

Components:
m1 m2 ρ θ Year
AB 5m5 7m8 69.7" 160° 2017
This star has the designation 41 Lyn but is assigned to UMa. At the time, when Flamsteed numbered the stars, the constellation boundaries were not exactly defined. Another example is 10 UMa, which is located in Lyn today.

Robert Zebahl
B 8x40, Bortle 7, NELM 5m0, SQM-L 19.2
Fairly well split with fainter component.

52 Her (**)

Name: 52 Her
Type: **
Constellation: Her
Coordinates: 16h49m14.20s / +45°59'00.40"

Components:
m1 m2 ρ θ Year
A1866 BC 9m5 9m6 0.3" 266° 2012
BU627 A-BC 4m8 8m4 2.2" 44° 2018

../images/binary-star-orbits/A1866-BC-orbit.jpg ../images/binary-star-orbits/BU627-A-BC-orbit.jpg

Robert Zebahl
102mm f/11, 280x, Bortle 6
BU627 (A-BC): At 160x the faint component is already beginning to be visible as brightening in the first diffraction ring. At 280x the brightening is quite clearly visible and appears partly clear as a small knot in the first diffraction ring.

59 And (**)

Name: 59 And, STF222
Type: **
Constellation: And
Coordinates: 02h10m52.83s / +39°02'22.40"

Components:
m1 m2 ρ θ Year
6m0 6m7 16.5" 36° 2018
Robert Zebahl
B 8x40, Bortle 7, SQM-L 19.0
Separated, but very tight. I used a tripod.

120mm f/5, 18x, Bortle 6, SQM-L 19.3
Well split with noticeable difference in brightness.

8" f/6, 100x, Bortle 4, NELM 6m0, SQM-L 20.9
Conditions in the target region: SQM-L 20.4
Nice and evident double star, easy to split. About 12 arcminutes NE there is NGC828 (v12.3m),

70 Oph (**)

Name: 70 Oph, P Oph, STF2272
Type: **
Constellation: Oph
Coordinates: 18h05m27.37s / +02°29'59.30"

Components:
m1 m2 ρ θ Year
AB 4m2 6m2 6.8" 121° 2018

../images/binary-star-orbits/STF2272-AB-orbit.jpg

Robert Zebahl
8" f/6, 80x, Bortle 5, SQM-L 20.7
Conditions in the target region: SQM-L 20.1
Well split at 80x. Brighter component appeared white, fainter one slightly orange.

164 And (**)

Name: 164 And, STF79
Type: **
Constellation: And
Coordinates: 01h00m03.56s / +44°42'47.70"

Components:
m1 m2 ρ θ Year
6m0 6m8 7.9" 195° 2018
Robert Zebahl
55mm f/9.1, 25x, Bortle 7, SQM-L 19.0
Beautiful double star, relatively tight with visible difference in brightness.

A 193 (**)

Name: A193
Type: **
Constellation: And
Coordinates: 23h01m23.99s / +46°38'18.00"

Components:
m1 m2 ρ θ Year
9m6 9m8 1.6" 176° 2017
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
Observed at 125x and 160x under urban conditions (Bortle 6-, SQM-L 19.0). Too faint to separate the components.

A 968 (**)

Name: A968
Type: **
Constellation: And
Coordinates: 02h31m15.90s / +47°02'32.10"

Components:
m1 m2 ρ θ Year
9m0 9m5 1.8" 27° 2018
Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
Clearly split, tight, slightly unequal.

A 1487 (**)

Name: A1487
Type: **
Constellation: And
Coordinates: 23h29m12.09s / +40°42'09.40"

Components:
m1 m2 ρ θ Year
9m0 9m5 1.1" 157° 2016
Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
At 125x clearly visible as figure '8' with equally bright components. At 160x comparable view.

A 1528 (**)

Name: A1528
Type: **
Constellation: And
Coordinates: 02h35m42.19s / +44°11'23.30"

Components:
m1 m2 ρ θ Year
9m4 9m6 1.6" 193° 2017
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
At 125x almost separated with visible difference in brightness. AT 160x rather faint, barely split, little difference in brightness.

A 1575 (**)

Name: A1575
Type: **
Constellation: Lyn
Coordinates: 07h03m01.14s / +54°02'55.40"

Components:
m1 m2 ρ θ Year
8m6 9m3 0.8" 283° 2016
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
Not clearly visible as double star.

152mm f/5.9, 225x, Bortle 6, SQM-L 19.4
2020-03-23: At 225x and 300x clearly elongated, partly seen as figure '8'.

A 2906 & STF314 (**)

Name: A2906 & STF314, WDS02529+5300
Type: **
Constellation: Per
Coordinates: 02h52m52.03s / +52°59'50.60"

Components:
m1 m2 ρ θ Year
A2906 AB 7m3 8m8 0.3" 115° 2018
STF314 AB-C 7m0 7m3 1.6" 316° 2018

../images/binary-star-orbits/A2906-AB-orbit.jpg ../images/binary-star-orbits/STF314-AB-C-orbit.jpg

Robert Zebahl
152mm f/5.9, 129x, Bortle 6, SQM-L 19.2
STF314 (AB-C): Beautifully separated, quite close together. Difference in brightness visible, but rather small. Easy to find and bright. Very nice.

AC 1 (**)

Name: AC1
Type: **
Constellation: And
Coordinates: 00h20m54.10s / +32°58'40.90"

Components:
m1 m2 ρ θ Year
7m3 8m3 1.9" 290° 2018

../images/binary-star-orbits/AC1-orbit.jpg

Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
Very attractive, relatively close with a clearly visible difference in brightness. In the immediate vicinity a brighter star shines in a lovely orange. Very nice contrast!

../sketches/2019-10-22_ac1.jpg

AC 14 (**)

Name: AC14
Type: **
Constellation: And
Coordinates: 01h28m19.28s / +42°46'56.00"

Components:
m1 m2 ρ θ Year
8m3 8m9 0.7" 93° 2018
Robert Zebahl
152mm f/5.9, 300x
Immediately visible as a double star, almost separated with little difference in brightness.

alpha Lib (**)

Name: alpha Lib, Zubenelgenubi, Kiffa Australis, Lanx Australis
Type: **
Constellation: Lib
Coordinates: 14h50m52.78s / -16°02'29.80"

Components:
m1 m2 ρ θ Year
SHJ186 AB 2m7 5m2 231.1" 314° 2012
AOT53 AC 2m7 12m5 275.6" 291° 2000
Component A: 9 Lib, alpha 2 Lib
Component B: 8 Lib, alpha 1 Lib
The standardized name Zubenelgenubi only refers to alpha 2 Lib.

beta Cyg (**)

Name: beta Cyg, 6 Cyg, Albireo, STFA43
Type: **
Constellation: Cyg
Coordinates: 19h30m43.29s / +27°57'34.90"

Components:
m1 m2 ρ θ Year
AB 3m2 4m7 34.6" 54° 2019
Robert Zebahl
B 8x40, Bortle 5, NELM 5m5
Well split, but I didn't recognised any color.

80mm f/6.25, 25x
One of the most beautiful double stars in the northern hemisphere. Differences in brightness and color (orange-blue) are brilliant! Even under urban conditions with small aperture an enjoyment!

beta Lyr (**)

Name: beta Lyr, 10 Lyr
Type: **
Constellation: Lyr
Coordinates: 18h50m04.79s / +33°21'45.60"

Components:
m1 m2 ρ θ Year
STFA39 AB 3m6 6m7 45.7" 149° 2017
BU293 AE 3m6 10m1 67.2" 317° 2015
BU293 AF 3m6 10m6 86.0" 18° 2015
Robert Zebahl
70mm f/5.7, 22x
At 22x and 57x the components A, B, E and F were easily seen. The B component appeared slightly bluish-silver at 22x, but at 57x the color was difficult to tell. All four components form a slightly curved 'Y' with the bright A component in the center.

102mm f/11, 62x, Bortle 6
Components A, B, E and F are easily visible. The two southern stars on the drawing do not belong to the system.

../sketches/2019-06-23_beta_lyr.jpg

BU 1 (**)

Name: BU1
Type: **
Constellation: Cas
Coordinates: 00h52m49.22s / +56°37'39.50"

Components:
m1 m2 ρ θ Year
AB 8m6 9m3 1.5" 83° 2016
AC 8m6 8m9 3.9" 134° 2017
AD 8m6 9m7 9.0" 194° 2017
AE 8m6 12m1 15.8" 333° 2015
CD 8m9 9m7 7.8" 220° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 7
AC: Easy to split with little difference in brightness.

70mm f/5.7, 57x, Bortle 7
AD: Relatively large angular distance with obviously fainter component.

BU 32 (**)

Name: BU32, 6 Ser
Type: **
Constellation: Ser
Coordinates: 15h21m02.00s / +00°42'55.20"

Components:
m1 m2 ρ θ Year
AB 5m5 8m8 3.4" 22° 2008
Robert Zebahl
102mm f/11, 224x
Not split. Tried at 224x and 280x. Companion probably too faint. I had sidewalk lighting in the immediate vicinity.

BU 67 (**)

Name: BU67
Type: **
Constellation: Cyg
Coordinates: 20h50m36.05s / +30°54'45.70"

Components:
m1 m2 ρ θ Year
6m8 9m9 1.5" 310° 2015
Robert Zebahl
152mm f/5.9, 270x, Bortle 6
Not split.

BU 130 (**)

Name: BU130, 90 Her
Type: **
Constellation: Her
Coordinates: 17h53m18.03s / +40°00'28.60"

Components:
m1 m2 ρ θ Year
5m3 8m8 1.6" 110° 2009
Robert Zebahl
120mm f/5, 300x, Bortle 6
Not split at 200x and 300x. I used a 120/600mm achromat.

BU 167 (**)

Name: BU167
Type: **
Constellation: Cyg
Coordinates: 21h36m13.98s / +30°03'19.50"

Components:
m1 m2 ρ θ Year
6m4 9m9 1.7" 89° 2016
Robert Zebahl
152mm f/5.9, 360x, Bortle 6-
The much fainter component was only occasionally visible as a clear brightening of the first diffraction ring. The diffraction ring itself was only indicated and not visible all around. Difficult.

BU 483 (**)

Name: BU483
Type: **
Constellation: And
Coordinates: 00h09m03.67s / +40°50'34.30"

Components:
m1 m2 ρ θ Year
AC 7m0 7m7 158.5" 268° 2015
Robert Zebahl
B 8x40, Bortle 7, SQM-L 19.0
Large distance with significant difference in brightness.

BU 533 (**)

Name: BU533
Type: **
Constellation: Per
Coordinates: 03h35m37.81s / +31°40'48.70"

Components:
m1 m2 ρ θ Year
AB 7m5 7m7 1.0" 222° 2018

../images/binary-star-orbits/BU533-AB-orbit.jpg

Robert Zebahl
152mm f/5.9, 225x, Bortle 6, SQM-L 19.2
At 129x clearly elongated, notched. At 225x just so separable with similarly bright components.

BU 535 (**)

Name: BU535, omicron Per, 38 Per, Atik
Type: **
Constellation: Per
Coordinates: 03h44m19.13s / +32°17'17.70"

Components:
m1 m2 ρ θ Year
3m9 6m7 1.1" 20° 2015
Robert Zebahl
152mm f/5.9, 300x, Bortle 6-, SQM-L 19.0
In steady moments the faint companion is clearly recognizable as a small brightening in the first diffraction ring of the primary component.

BU 560 (**)

Name: BU560
Type: **
Constellation: Aur
Coordinates: 05h47m24.87s / +29°39'26.90"

Components:
m1 m2 ρ θ Year
7m8 8m2 1.7" 124° 2019

../images/binary-star-orbits/BU560-orbit.jpg

Robert Zebahl
70mm f/5.7, 100x
Clearly visible as a double star with overlapping diffraction disks (figure '8') and small difference in brightness.
152mm f/5.9, 129x, Seeing 2-3/5
Separated with very little difference in brightness, relatively tight. Overall easy.

BU 728 (**)

Name: BU728
Type: **
Constellation: And
Coordinates: 23h52m09.63s / +43°30'31.60"

Components:
m1 m2 ρ θ Year
AB 8m7 8m9 1.3" 10° 2016
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
At 125x two overlapping Airy disks with a small difference in brightness are visible. At 160x slightly better and almost separated.

BU 1008 (**)

Name: BU1008, eta Gem, 7 Gem, Propus
Type: **
Constellation: Gem
Coordinates: 06h14m52.69s / +22°30'24.60"

Components:
m1 m2 ρ θ Year
3m5 6m2 1.8" 258° 2017

../images/binary-star-orbits/BU1008-orbit.jpg

Robert Zebahl
152mm f/5.9, 225x, Bortle 6, SQM-L 19.3, Seeing 3/5
Already comparatively easy at 180x. The faint companion can be seen well as a quite distinct, slightly elongated, partly round brightening. At 225x and above it becomes easy and immediately apparent, even if the diffraction rings of the primary component are not permanently visible due to the seeing. The primary component was shining in a bright orange.

BU 1053 (**)

Name: BU1053
Type: **
Constellation: Aur
Coordinates: 05h53m28.64s / +37°20'20.70"

Components:
m1 m2 ρ θ Year
6m9 8m8 1.9" - 2019

../images/binary-star-orbits/BU1053-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x
Border observation! Companion is temporarily visible in the correct position angle as an extremely dim brightening of the first diffraction ring of the primary component.

COU 240 (**)

Name: COU240
Type: **
Constellation: Peg
Coordinates: 22h56m23.71s / +22°57'21.20"

Components:
m1 m2 ρ θ Year
7m7 8m8 0.8" 289° 2017
Robert Zebahl
152mm f/5.9, 300x
Borderline observation with rather less good seeing. The fainter companion could be detected in the correct position angle to some extent as a small bulge in the diffraction disk.

CSN 12 (**)

Name: CSN12
Type: **
Constellation: Aql
Coordinates: 19h16m55.23s / +05°10'07.10"

Components:
m1 m2 ρ θ Year
AN 4m7 5m8 9.1" 285° 2000
Robert Zebahl
70mm f/5.7, 22x
2019-07-03: Absolutely no star with the given magnitude visible at this position. An error in the WDS or is this a variable one?

delta Cep (**)

Name: delta Cep, 27 Cep
Type: **
Constellation: Cep
Coordinates: 22h29m10.25s / +58°24'54.70"

Components:
m1 m2 ρ θ Year
BU702 AB 4m2 13m0 21.5" 282° 2015
STFA58 AC 4m2 6m1 41.0" 191° 2018
DAL45 AD 4m2 13m9 109.0" 39° 2015
DAL45 DE 13m9 14m0 1.4" 23° 2008
Robert Zebahl
55mm f/9.1, 27x, Bortle 6
AC: At 27x easy to separate, rather wide apart with clear difference in brightness. At 38x the colors are slightly better visible: A shines in bright orange, B appears rather grey-bluish.

80mm f/6.25, 25x
AC: Obvious difference in brightness and color. Brighter component slightly orange, weaker bluish. Could be Albireo's little brother ;)

EHR 16 (**)

Name: EHR16, lambda Aql, 16 Aql
Type: **
Constellation: Aql
Coordinates: 19h06m14.95s / -04°52'56.40"

Components:
m1 m2 ρ θ Year
AB 3m5 7m5 12.5" 30° 2009
Robert Zebahl
70mm f/5.7, 133x
2019-07-03: The faint B component could not be seen for sure.

epsilon Lyr (**)

Name: epsilon Lyr
Type: **
Constellation: Lyr
Coordinates: 18h44m20.34s / +39°40'12.40"

Components:
m1 m2 ρ θ Year
STFA37 AB-CD 4m7 4m6 209.5" 172° 2016
STFA37 AI 5m2 10m1 149.5" 137° 2015
STF2382, 4 Lyr, epsilon 1 Lyr AB 5m2 6m1 2.2" 346° 2018
STF2383, 5 Lyr, epsilon 2 Lyr CD 5m2 5m4 2.4" 75° 2018

../images/binary-star-orbits/STF2382-AB-orbit-solution-1.jpg ../images/binary-star-orbits/STF2382-AB-orbit-solution-2.jpg ../images/binary-star-orbits/STF2383-CD-orbit.jpg

Robert Zebahl
55mm f/9.1, 59x
STF2382 (AB): At 42x slightly elongated, at 59x elongated and obviously notched.

55mm f/9.1, 59x
STF2383 (CD): At 42x clearly elongated, but without any visible notch. At 59x split with touching diffraction disks.

70mm f/5.7, 57x
STF2382 (AB): Obviously seen as figure '8'.

70mm f/5.7, 57x
STF2383 (CD): Split, but extremely tight with almost touching diffraction disks.
102mm f/11, 125x, Bortle 6, SQM-L 19.4
Stunning view of the components A-D and I!

../sketches/2019-06-26_epsilon_lyr.jpg

ES 4 (**)

Name: ES4
Type: **
Constellation: And
Coordinates: 01h31m05.02s / +43°37'14.60"

Components:
m1 m2 ρ θ Year
8m1 9m1 2.8" 101° 2016
Robert Zebahl
70mm f/5.7, 128x
Not split. I probably didn't recognised the fainter component. The angular distance shouldn't be a problem.

ES 2076 (**)

Name: ES2076
Type: **
Constellation: And
Coordinates: 23h00m56.79s / +37°13'54.10"

Components:
m1 m2 ρ θ Year
9m5 9m5 1.8" 162° 2016
Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
Observation under urban conditions (Bortle 6-, SQM-L 19.0). Too faint to separate.

eta Cas (**)

Name: eta Cas, 24 Cas
Type: **
Constellation: Cas
Coordinates: 00h49m06.29s / +57°48'54.70"

Components:
m1 m2 ρ θ Year
STF60 AB 3m5 7m4 13.4" 326° 2019
STF60 AC 3m5 11m4 225.0" 260° 2000
STF60 AD 3m5 12m8 189.4" 354° 2011
STF60 AE 3m5 10m2 75.6" 126° 2015
STF60 AF 3m5 11m5 378.3" 276° 2000
STF60 AG 3m5 9m5 419.7" 259° 2012
STF60 AH 3m5 8m4 701.1" 355° 2012
SMR2 AI 3m5 11m6 90.3" 73° 2012
SMR2 AJ 3m5 12m3 237.1" 262° 2012

../images/binary-star-orbits/STF60-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x
AB: Easy to split with big difference in brightness. Fainter component appeared deep orange to slightly red colored, brighter component tends to be more slightly yellowish.

gamma Ari (**)

Name: gamma Ari, STF180
Type: **
Constellation: Ari
Coordinates: 01h53m31.76s / +19°17'38.60"

Components:
m1 m2 ρ θ Year
AB 4m5 4m6 7.4" 2018
Robert Zebahl
8" f/6, 80x, Bortle 3-, SQM-L 21.3
Nice, obvious double star. Both components have similar brightness and appeared white.

gamma Her (**)

Name: gamma Her, 20 Her
Type: **
Constellation: Her
Coordinates: 16h21m55.24s / +19°09'10.90"

Components:
m1 m2 ρ θ Year
DRS58 AD 2m9 8m1 8.3" 176° 2010
SHJ227 AB 3m8 10m1 43.3" 226° 2013
SHJ227 BC 10m1 13m3 82.0" 298° 2015
Robert Zebahl
102mm f/11, 280x, Bortle 6, SQM-L 19.4
AD: It is already the second attempt at this double star. There was nothing perceptible at the best of intentions, which indicates a double star.

H 1 48 (**)

Name: H1 48
Type: **
Constellation: Cep
Coordinates: 21h13m42.46s / +64°24'15.10"

Components:
m1 m2 ρ θ Year
7m2 7m3 0.7" 244° 2018

../images/binary-star-orbits/H1-48-orbit.jpg

Robert Zebahl
152mm f/5.9, 270x, Bortle 6-
Clearly elongated, of equal brightness with partly visible, slight notching.

H 5 12 (**)

Name: H5 12, 9 Ari, lambda Ari
Type: **
Constellation: Ari
Coordinates: 01h57m55.71s / +23°35'45.80"

Components:
m1 m2 ρ θ Year
AB 4m8 6m7 37.3" 48° 2018
Robert Zebahl
70mm f/5.7, 15x, Bortle 6-
Easy to split with large distance and difference in brightness.

H 5 82 (**)

Name: H5 82
Type: **
Constellation: Cas
Coordinates: 00h47m24.62s / +51°05'45.90"

Components:
m1 m2 ρ θ Year
AB 8m0 8m3 56.8" 75° 2018
Robert Zebahl
70mm f/5.7, 26x, Bortle 7
Almost equally bright components with large angular distance.

HJ 3288 (**)

Name: HJ3288
Type: **
Constellation: Gem
Coordinates: 07h02m18.43s / +12°34'54.20"

Components:
m1 m2 ρ θ Year
7m3 8m7 38.5" 247° 2015
Robert Zebahl
70mm f/5.7, 22x, Bortle 6
Easy to separate with moderate angular distance and a significant difference in brightness. Slight difference in color: white-yellowish, slightly orange. Nice view together with the double star STF1007 and HD52976, which appears in a bright orange. Sketched together with STF1007.

../sketches/2019-12-18_stf1007_hj3288.jpg

HJ 3945 (**)

Name: HJ3945, 145 CMa, Winter Albireo
Type: **
Constellation: CMa
Coordinates: 07h16m36.84s / -23°18'56.10"

Components:
m1 m2 ρ θ Year
AB 5m0 5m8 26.8" 50° 2015
Robert Zebahl
120mm f/5, 23x
Evident, easy to split at large angular distance. Brighter component appeared very orange, fainter one bluish.

HLD 56 (**)

Name: HLD56
Type: **
Constellation: And
Coordinates: 22h59m42.14s / +41°49'25.20"

Components:
m1 m2 ρ θ Year
9m3 9m4 1.3" 92° 2016
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
At 125x clearly visible as figure '8' with slight difference in brightness. Almost split at 160x.

HO 306 (**)

Name: HO306
Type: **
Constellation: And
Coordinates: 00h48m06.71s / +25°32'54.30"

Components:
m1 m2 ρ θ Year
9m6 9m9 1.5" 159° 2016
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
Pretty faint and tight with visible difference in brightness.

HU 103 (**)

Name: HU103
Type: **
Constellation: Per
Coordinates: 03h45m22.61s / +49°51'42.40"

Components:
m1 m2 ρ θ Year
AB 8m7 8m9 1.2" 203° 2018
Robert Zebahl
152mm f/5.9, 225x, Bortle 6-, SQM-L 19.0
At 100x slightly elongated, at 129x elongated, notched. At 225x clearly separated, but tight with little difference in brightness.

HU 544 (**)

Name: HU544
Type: **
Constellation: Per
Coordinates: 03h15m48.70s / +50°57'21.20"

Components:
m1 m2 ρ θ Year
6m7 8m2 1.7" 103° 2018

../images/binary-star-orbits/HU544-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.2
Clearly seen as figure '8' with noticeable difference in brightness.
152mm f/5.9, 129x, Bortle 6-, SQM-L 19.0
Wonderfully separated in equally beautiful star surroundings! Clear difference in brightness visible. To the east there is a brighter star, which shines yellowish-orange. HU544 itself seems rather cool in color.

../sketches/2019-11-23_hu544.jpg

IC 5006 (**)

../dss/dss2red_202347.00_+062655.00_5_web.jpg
Image source: DSS II (red) - 5×5'
Name: IC5006
Type: **
Constellation: Aql
Coordinates: 20h23m47.00s / +06°26'55.00"

Components:
m1 m2 ρ θ Year
14m5 15m1 6.0" 210.0° -
Robert Zebahl
8" f/6, 150x, Bortle 4, NELM 5m7+, SQM-L 20.9
Conditions in the target region: NELM 5m4+, SQM-L 20.6
I saw this 'double star' with averted vision just as a faint, stellar brightening.
MODERATE

KR 11 (**)

Name: KR11
Type: **
Constellation: Cas
Coordinates: 01h19m40.95s / +61°34'44.40"

Components:
m1 m2 ρ θ Year
9m6 9m7 2.0" 59° 2017
Robert Zebahl
152mm f/5.9, 129x
Rather faint double star. Easily split with equally bright components.

KR 60 (**)

Name: KR60, DO Cep, Kruger 60
Type: **
Constellation: Cep
Coordinates: 22h27m59.20s / +57°41'43.80"

Components:
m1 m2 ρ θ Year
AB 9m9 11m4 1.5" 266° 2016
A detailed article about Kruger 60 was published in the "Journal of Double Star Observations" by Wilfried R.A. Knapp and John Nanson. Another article is about the origin of the comet 2I/Borisov (C/2019 Q4) in connection with Kruger 60.

../images/binary-star-orbits/KR60-AB-orbit.jpg

Robert Zebahl
152mm f/5.9, 150x, Bortle 6-
Observed at magnifications between 129x and 300x. The seeing and transparency (Bortle 6-) were only average. The rather faint B component seemed to appear in few moments.

152mm f/5.9, 150x, Bortle 6, SQM-L 19.1, Seeing 3/5
The seeing was more average (3/5). Observation under suburban conditions (Bortle 6, SQM-L 19.1). Initially observed at 270x, later at 300x. The extremely faint companion was always visible at the same position if the air was steady enough. Difficult because of the low magnitude!

LEP 103 (**)

Name: LEP103
Type: **
Constellation: Cep
Coordinates: 21h54m14.50s / +66°43'54.20"

Components:
m1 m2 ρ θ Year
7m2 8m0 4.1" 213° 2000
Robert Zebahl
152mm f/5.9, 100x, Bortle 4, SQM-L 21.0
The brightness of this double star does not match the data in the WDS. I also couldn't separate anything here. A mistake in the WDS?

LSL 1 (**)

Name: LSL1, Lassell 1
Type: **
Constellation: Cyg
Coordinates: 21h34m45.16s / +32°04'42.60"

Components:
m1 m2 ρ θ Year
AB 10m6 11m7 82.1" 82° 2015
AC 10m6 12m1 106.1" 127° 2015
AD 10m6 11m9 21.2" 134° 2015
AE 10m6 13m5 10.5" 331° 2015
BF 11m7 12m1 18.4" 210° 2015
CG 12m1 14m4 11.5" 199° 2015
Robert Zebahl
152mm f/5.9, 180x
Comparatively wide pairs with rather faint components. Observation at nearly full moon. Components A & D easy, B relatively well and C & F quite faint. Components E & G not visible. Overall unspectacular under these conditions.

mu Boo (**)

Name: mu Boo, 51 Boo, Alkalurops
Type: **
Constellation: Boo
Coordinates: 15h24m29.54s / +37°22'37.10"

Components:
m1 m2 ρ θ Year
CHR181, mu 1 Boo Aa-Ab 4m3 None 0.1" 188° 2012
STFA28, mu 1 Boo AB 4m3 7m1 109.0" 172° 2018
STF1938, mu 2 Boo Ba-Bb 7m1 7m6 2.3" 2019

../images/binary-star-orbits/CHR181-Aa-Ab-orbit.jpg ../images/binary-star-orbits/STF1938-Ba-Bb-orbit.jpg

Robert Zebahl
B 8x40, Bortle 7, NELM 5m0, SQM-L 19.2
STFA28 (AB): Easily split with obvious difference in brightness.

70mm f/5.7, 22x, Bortle 6, SQM-L 19.2
STFA28 (AB): Evident, very wide apart and unequal. A: white-yellowish, B: grey.

102mm f/11, 125x, Bortle 6-, SQM-L 19.2
STF1938 (Ba-Bb): Beautiful view! This triple system includes STFA 28 and STF 1938.

../sketches/2019-04-04_mu_boo.jpg

120mm f/5, 23x, Bortle 6, NELM 5m0+, SQM-L 19.4
STFA28 (AB): Easy to split with large angular distance and noticeable difference in brightness.

mu Cyg (**)

Name: mu Cyg, 78 Cyg, STF2822
Type: **
Constellation: Cyg
Coordinates: 21h44m08.57s / +28°44'33.40"

Components:
m1 m2 ρ θ Year
AB 4m8 6m2 1.6" 321° 2018

../images/binary-star-orbits/STF2822-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 128x
At 128x I was able to see this double at least elongated.
8" f/6, 171x, Bortle 5, NELM 5m7, SQM-L 20.6
Quite well split with noticeable fainter component.

mu Dra (**)

Name: mu Dra, 21 Dra, Alrakis, Arrakis
Type: **
Constellation: Dra
Coordinates: 17h05m20.20s / +54°28'14.30"

Components:
m1 m2 ρ θ Year
STF2130 AB 5m7 5m7 2.5" 2018
BU1088 AC 5m7 13m7 12.2" 174° 2015

../images/binary-star-orbits/STF2130-AB-orbit.jpg

Robert Zebahl
102mm f/11, 125x, Bortle 6
AB: Easy to separate. Beautiful sight. Components equally bright with no discernible color difference.

mu Her (**)

Name: mu Her, 86 Her
Type: **
Constellation: Her
Coordinates: 17h46m27.51s / +27°43'14.30"

Components:
m1 m2 ρ θ Year
A-BC 3m5 9m8 35.5" 249° 2015
Robert Zebahl
120mm f/5, 86x, Bortle 6
A-BC: Easy, pretty wide, unequal pair. A appeared yellowish-orange, BC was barely visible with direct vision.

NGC 6933 (**)

../dss/dss2blue_203338.50_+072325.00_5_web.jpg
Image source: DSS II (blue) - 5×5'
Name: NGC6933
Type: **
Constellation: Del
Coordinates: 20h33m38.50s / +07°23'25.00"

Components:
m1 m2 ρ θ Year
10m8 12m5 30.0" 215.0° -
I guess it is just an optical double star. At least I could not find any entry in the 'Washington Double Star Catalog' (WDS). Located west of the globular cluster NGC6935 in an angular distance of less than 10 arcminutes.

Robert Zebahl
8" f/6, 80x, Bortle 4, NELM 5m7+, SQM-L 20.9
Conditions in the target region: NELM 5m4+, SQM-L 20.6
Easily split, but rather unspectacular. Just for completeness ;-)
EASY

SHJ 145 (**)

Name: SHJ145, delta Crv, 7 Crv, Algorab
Type: **
Constellation: Crv
Coordinates: 12h29m51.86s / -16°30'55.60"

Components:
m1 m2 ρ θ Year
AB 3m0 8m5 24.0" 215° 2015
Robert Zebahl
70mm f/5.7, 47x, Bortle 6, SQM-L 19.5
Large difference in brightness and pretty wide apart. Primary component appeared white-bluish. The B component was too faint for seeing colors.

SHJ 146 (**)

Name: SHJ146
Type: **
Constellation: Vir
Coordinates: 12h31m14.61s / +01°19'37.00"

Components:
m1 m2 ρ θ Year
AB 7m7 8m7 49.5" 290° 2017
Robert Zebahl
70mm f/5.7, 33x, Bortle 6, SQM-L 19.5
Visible difference in brightness and color. I couldn't precisely define the colors itself, but A appeared rather orange, B rather bluish.

102mm f/11, 28x
Pretty wide pair with visible difference in brightness and lovely color contrast. A: pale orange, B: light blue.

sigma CrB (**)

Name: sigma CrB, 17 CrB, STF2032
Type: **
Constellation: CrB
Coordinates: 16h14m40.85s / +33°51'31.00"

Components:
m1 m2 ρ θ Year
AB 5m6 6m5 7.2" 239° 2019

../images/binary-star-orbits/STF2032-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 22x, Bortle 4, SQM-L 20.9
At 22x clearly separated, but very close with a clear difference in brightness. At 57x easy without any noticeable difference in color.

SIN 128 (**)

Name: SIN128
Type: **
Constellation: Aur
Coordinates: 06h01m14.73s / +31°32'28.10"

Components:
m1 m2 ρ θ Year
AC 7m3 7m6 2.6" 193° 1985
Robert Zebahl
70mm f/5.7, 133x
Even at high magnification there are no indications of a double star. Also the brightness seemed to be less than stated!?

STF 7 (**)

Name: STF7
Type: **
Constellation: Cas
Coordinates: 00h11m38.91s / +55°57'40.90"

Components:
m1 m2 ρ θ Year
8m0 8m5 1.3" 210° 2017
Robert Zebahl
152mm f/5.9, 210x
Clearly separated with rather close components. Slightly unequal. Pretty double.

STF 12 (**)

Name: STF12, 35 Psc
Type: **
Constellation: Psc
Coordinates: 00h14m58.84s / +08°49'15.50"

Components:
m1 m2 ρ θ Year
6m1 7m5 11.5" 148° 2018
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
At 22x pretty bright but uneven pair with relatively close components. At 44x the brighter component looked slightly yellowish, the fainter one slightly bluish. The double star could be observed together with STF22 (38 Psc) in the same field of view and stands in nice contrast to it.

STF 22 (**)

Name: STF22, 38 Psc
Type: **
Constellation: Psc
Coordinates: 00h17m24.50s / +08°52'34.80"

Components:
m1 m2 ρ θ Year
AB-C 7m1 7m7 3.9" 235° 2017
AB-D 7m1 11m5 66.8" 151° 2005
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.1
AB-C: At 44x separated with almost touching diffraction disks and small difference in brightness. At 57x clearly separated, but still quite close together. It stands in beautiful contrast to the nearby double star STF12 (35 Psc).

STF 24 (**)

Name: STF24
Type: **
Constellation: And
Coordinates: 00h18m30.59s / +26°08'25.10"

Components:
m1 m2 ρ θ Year
7m8 8m4 5.1" 247° 2017
Robert Zebahl
70mm f/5.7, 66x, Bortle 6-
Well split with visible difference in brightness.

STF 33 (**)

Name: STF33
Type: **
Constellation: And
Coordinates: 00h30m58.47s / +34°05'53.90"

Components:
m1 m2 ρ θ Year
8m8 8m9 2.8" 213° 2017
Robert Zebahl
70mm f/5.7, 128x, Bortle 4-, SQM-L 20.9
Components equally bright, easy to split.

STF 46 (**)

Name: STF46, 55 Psc
Type: **
Constellation: Psc
Coordinates: 00h39m55.57s / +21°26'18.60"

Components:
m1 m2 ρ θ Year
5m6 8m5 6.6" 195° 2015
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.1
Clearly separated, but large difference in brightness. The companion appeared only as a tiny, faint star. The primary component sparkled in light orange.

STF 48 (**)

Name: STF48
Type: **
Constellation: Cas
Coordinates: 00h42m40.01s / +71°21'57.30"

Components:
m1 m2 ρ θ Year
AB 7m8 8m1 5.5" 334° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
At 22x almost split, clearly elongated, notched. At 31x split, but very close together, almost equally bright. At 57x easily separable with very small difference in brightness. The fainter companion appeared slightly orange.

STF 55 (**)

Name: STF55
Type: **
Constellation: And
Coordinates: 00h44m22.95s / +33°37'05.60"

Components:
m1 m2 ρ θ Year
8m3 8m9 2.3" 331° 2016
Robert Zebahl
70mm f/5.7, 128x, Bortle 7+, SQM-L 18.8
Well split with noticeable difference in brightness.

STF 59 (**)

Name: STF59
Type: **
Constellation: Cas
Coordinates: 00h47m59.03s / +51°26'41.20"

Components:
m1 m2 ρ θ Year
AB 7m2 8m1 2.4" 151° 2018
Robert Zebahl
70mm f/5.7, 100x, Bortle 7
At 57x elongated, at 100x barely, at 128x clearly split with noticeable difference in brightness.

STF 65 (**)

Name: STF65
Type: **
Constellation: Cas
Coordinates: 00h52m45.61s / +68°51'59.30"

Components:
m1 m2 ρ θ Year
8m0 8m0 3.2" 220° 2017
Robert Zebahl
70mm f/5.7, 57x, Bortle 7
Clearly split with equally bright components.

STF 72 (**)

Name: STF72
Type: **
Constellation: And
Coordinates: 00h54m37.50s / +39°10'09.70"

Components:
m1 m2 ρ θ Year
8m4 9m3 23.3" 173° 2015
Robert Zebahl
152mm f/5.9, 22x, Bortle 6, SQM-L 19.3
Easy with moderate difference in brightness. Both components appeared orange, the fainter one slightly more intense. The color was well visible at 69x.

STF 73 (**)

Name: STF73, 36 And
Type: **
Constellation: And
Coordinates: 00h54m58.02s / +23°37'42.40"

Components:
m1 m2 ρ θ Year
AB 6m1 6m5 1.1" 334° 2018
Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
Clearly visible as figure '8' with a rather small difference in brightness.

152mm f/5.9, 300x
Split with little gap in between and little difference in brightness. Seeing was not really good.

STF 98 (**)

Name: STF98
Type: **
Constellation: Psc
Coordinates: 01h12m52.98s / +32°04'31.70"

Components:
m1 m2 ρ θ Year
AB 7m0 8m1 20.0" 250° 2018
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
Easy to separate at 22x, clear difference in brightness at moderate distance. In terms of color, the two components appeared slightly different. At 44x A appeared white-yellowish, B slightly reddish.

STF 104 (**)

Name: STF104
Type: **
Constellation: And
Coordinates: 01h16m57.09s / +38°27'38.70"

Components:
m1 m2 ρ θ Year
8m0 9m8 13.4" 323° 2015
Robert Zebahl
152mm f/5.9, 69x, Bortle 6, SQM-L 19.3
Easy, rather close pair, but with a clear difference in brightness. Primary component appeared slightly orange, companion slightly grey-bluish.

STF 105 (**)

Name: STF105
Type: **
Constellation: Cas
Coordinates: 01h18m57.50s / +66°09'28.00"

Components:
m1 m2 ρ θ Year
AB 8m8 9m8 3.0" 185° 2016
Robert Zebahl
70mm f/5.7, 100x, Bortle 7
Clearly split with visible difference in brightness.

STF 108 (**)

Name: STF108
Type: **
Constellation: And
Coordinates: 01h18m47.00s / +37°23'10.60"

Components:
m1 m2 ρ θ Year
6m5 9m6 6.4" 62° 2017
Robert Zebahl
120mm f/5, 75x, Bortle 6, SQM-L 19.1
Easily split with big difference in brightness.

152mm f/5.9, 69x, Bortle 6, SQM-L 19.3
Easy and pretty uneven. Primary component appeared slightly yellowish.

STF 136 (**)

Name: STF136, 100 Psc
Type: **
Constellation: Psc
Coordinates: 01h34m51.61s / +12°33'31.20"

Components:
m1 m2 ρ θ Year
AB 7m3 8m3 15.7" 77° 2016
AC 7m3 13m6 76.9" 312° 2015
AD 7m3 11m6 124.5" 2015
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
AB: At 22x easy to separate with well visible difference in brightness. A difference in color is visible, but the assignment of colors was difficult. At 44x A appeared slightly orange, B rather bluish.

STF 141 (**)

Name: STF141
Type: **
Constellation: And
Coordinates: 01h40m03.42s / +38°58'10.70"

Components:
m1 m2 ρ θ Year
8m3 8m6 1.7" 303° 2018
Robert Zebahl
102mm f/11, 125x, Bortle 6-, SQM-L 19.0
Clearly separated, but still very close. Slightly uneven.

STF 149 (**)

Name: STF149
Type: **
Constellation: And
Coordinates: 01h44m30.83s / +39°57'31.10"

Components:
m1 m2 ρ θ Year
8m2 9m3 1.4" 81° 2018
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
At 125x almost split, noticeably uneven. At 160x split, but pretty tight.

STF 155 (**)

Name: STF155
Type: **
Constellation: Psc
Coordinates: 01h44m15.19s / +09°29'02.70"

Components:
m1 m2 ρ θ Year
AB 7m9 8m0 4.9" 325° 2018
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.1
Lovely embedded in a small group of stars. The components showed a small difference in brightness and were very close together.

../sketches/2019-10-24_stf155.jpg

STF 162 (**)

Name: STF162
Type: **
Constellation: Per
Coordinates: 01h49m15.47s / +47°53'47.10"

Components:
m1 m2 ρ θ Year
AB 6m5 7m2 2.0" 199° 2018
AC 6m5 9m2 20.3" 178° 2018
AD 6m5 10m0 138.7" 96° 2007
BC 7m2 9m2 19.2" 177° 2018
Robert Zebahl
70mm f/5.7, 100x
AB: At 100x partly split, otherwise '8'-shaped. At 128x clearly split. Difference in brightness noticeable.

STF 163 (**)

Name: STF163
Type: **
Constellation: Cas
Coordinates: 01h51m16.93s / +64°51'17.90"

Components:
m1 m2 ρ θ Year
AB 6m8 9m1 34.5" 38° 2018
Robert Zebahl
70mm f/5.7, 20x, Bortle 7+, SQM-L 18.8
Easily split at 20x. From 44x the brighter component was orange colored, the fainter one tends to be more bluish.

STF 170 (**)

Name: STF170
Type: **
Constellation: Cas
Coordinates: 01h55m27.35s / +76°13'28.40"

Components:
m1 m2 ρ θ Year
7m5 8m2 3.2" 244° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 7
At 57x barely split with noticeable difference in brightness. At 128x easy split.

STF 178 (**)

Name: STF178
Type: **
Constellation: Ari
Coordinates: 01h52m02.54s / +10°48'38.10"

Components:
m1 m2 ρ θ Year
8m2 8m2 3.0" 205° 2018
Robert Zebahl
63mm f/13.3, 67x, Bortle 6-, SQM-L 19.0
Clearly split, tight, apparently equally bright components.

70mm f/5.7, 100x, Bortle 7+, SQM-L 18.8
Split with equally bright components.

STF 182 (**)

Name: STF182
Type: **
Constellation: Cas
Coordinates: 01h56m23.56s / +61°16'52.00"

Components:
m1 m2 ρ θ Year
AB 8m3 8m3 3.6" 125° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 7
At 44x almost split. At 57x equally bright components visible.

STF 205 (**)

Name: STF205, gamma And, 57 And, Alamak
Type: **
Constellation: And
Coordinates: 02h03m53.92s / +42°19'47.50"

Components:
m1 m2 ρ θ Year
A-BC 2m3 5m0 9.4" 63° 2016
Robert Zebahl
63mm f/13.3, 42x, Bortle 6-, SQM-L 19.0
Easy to split with quite large difference in brightness.

152mm f/5.9, 100x, Bortle 6, SQM-L 19.3
Very easy. A: orange, BC: rather white.

STF 212 (**)

Name: STF212
Type: **
Constellation: Ari
Coordinates: 02h06m14.96s / +25°06'31.00"

Components:
m1 m2 ρ θ Year
8m3 8m7 1.9" 162° 2018
Robert Zebahl
63mm f/13.3, 168x, Bortle 6-, SQM-L 19.0
Not split, but partially seen as an '8'. Overall the double star appeared rather faint and both components seemed to be similarly bright.

70mm f/5.7, 128x, Bortle 7+, SQM-L 18.8
Barely split with slight difference in brightness.

STF 219 (**)

Name: STF219
Type: **
Constellation: Tri
Coordinates: 02h10m16.10s / +33°21'55.20"

Components:
m1 m2 ρ θ Year
8m0 8m9 11.7" 186° 2015
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, NELM 5m0+, SQM-L 19.1
Well separated with noticeable difference in brightness.

STF 227 (**)

Name: STF227, iota Tri, 6 Tri
Type: **
Constellation: Tri
Coordinates: 02h12m22.28s / +30°18'11.10"

Components:
m1 m2 ρ θ Year
5m3 6m7 3.7" 69° 2016
Robert Zebahl
70mm f/5.7, 57x
At 44x even separable with a clear difference in brightness, whereby the companion is almost outshone by the primary component. At 57x easy to separate. Primary component shines in bright orange, companion slightly orange. Beautiful sight together with STF232 in one field of view!

../sketches/2019-12-12_6_tri_stf232.jpg

STF 232 (**)

Name: STF232
Type: **
Constellation: Tri
Coordinates: 02h14m42.16s / +30°23'41.20"

Components:
m1 m2 ρ θ Year
7m8 7m9 6.5" 66° 2016
Robert Zebahl
70mm f/5.7, 22x
Very beautiful view! With all used magnifications together with iota Tri (6 Tri) in one field of view. Separable at 22x, but the components are still quite close together and appear similarly bright. At 44x easy to separate with little difference in brightness. At 57x a very small color difference is visible without being able to clearly name the colors. STF232 was sketched together with 6 Tri.

STF 239 (**)

Name: STF239
Type: **
Constellation: Tri
Coordinates: 02h17m25.29s / +28°44'42.10"

Components:
m1 m2 ρ θ Year
7m1 7m8 13.6" 212° 2017
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, NELM 5m0+, SQM-L 19.1
Easy to split, large distance, noticeable difference in brightness.

STF 245 (**)

Name: STF245
Type: **
Constellation: And
Coordinates: 02h18m36.27s / +40°16'43.70"

Components:
m1 m2 ρ θ Year
AB 7m3 8m0 11.0" 294° 2015
Robert Zebahl
120mm f/5, 50x, Bortle 6, SQM-L 19.3
Both components well seen with noticeable difference in brightness.

STF 249 (**)

Name: STF249
Type: **
Constellation: And
Coordinates: 02h21m35.66s / +44°35'59.70"

Components:
m1 m2 ρ θ Year
7m2 9m0 2.4" 197° 2018
Robert Zebahl
63mm f/13.3, 168x, Bortle 6-, SQM-L 19.0
Not separated. The diffraction disk showed again and again irregularities, which indicated a double star.

STF 262 (**)

Name: STF262, iota Cas
Type: **
Constellation: Cas
Coordinates: 02h29m03.96s / +67°24'08.70"

Components:
m1 m2 ρ θ Year
AB 4m6 6m9 2.9" 230° 2017
AC 4m6 9m1 6.7" 117° 2015
AD 4m6 8m5 210.9" 60° 2016

../images/binary-star-orbits/STF262-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 27x, Bortle 7
Only the D component was well visible. The components B & C were not visible even at magnifications up to 167x. The sky was clearly brightened (Bortle 7).

70mm f/5.7, 120x, Bortle 6-
Components A, B and C pretty close together, D far apart. Component B appeared slightly elongated on the first diffraction ring of the primary component. Rewarding!

../sketches/2019-08-25_iota_cas.jpg

152mm f/5.9, 129x
Component D easy to see even at lowest magnification. Component C is also easily visible at 49x. At 69x the component B is indicated, at 100x clearly visible. C appears slightly grey-bluish and obviously fainter than B. Grand sight at 129x!

STF 268 (**)

Name: STF268
Type: **
Constellation: Per
Coordinates: 02h29m24.96s / +55°32'10.50"

Components:
m1 m2 ρ θ Year
6m7 8m5 2.9" 131° 2018
Robert Zebahl
70mm f/5.7, 80x, Bortle 6
At 67x the faint companion can be guessed and is still slightly outshined by the primary component. At 80x and 100x relatively well separable with clear difference in brightness, but close together. The companion is close to the first diffraction ring of the primary component.

152mm f/5.9, 129x, Bortle 6, SQM-L 19.2
Easily separable with significant difference in brightness. The fainter companion is nicely separated from the primary component and visible as a tiny star.

STF 272 (**)

Name: STF272
Type: **
Constellation: Per
Coordinates: 02h33m08.71s / +58°27'44.90"

Components:
m1 m2 ρ θ Year
8m3 8m4 1.9" 216° 2017
Robert Zebahl
152mm f/5.9, 129x, Bortle 6, SQM-L 19.2
Easy to separate, but close together with very little difference in brightness. Beautiful view. Double star stands in a half arc of stars.

STF 291 (**)

Name: STF291
Type: **
Constellation: Ari
Coordinates: 02h41m06.59s / +18°48'00.70"

Components:
m1 m2 ρ θ Year
AB 7m7 7m5 3.4" 118° 2017
AC 7m7 9m5 65.5" 242° 2015
Robert Zebahl
70mm f/5.7, 57x
AB: At 44x almost, at 57x clearly split, but still very tight with rather small difference in brightness.

STF 295 (**)

Name: STF295, 84 Cet
Type: **
Constellation: Cet
Coordinates: 02h41m14.00s / -00°41'44.40"

Components:
m1 m2 ρ θ Year
5m8 9m7 3.6" 301° 2012

../images/binary-star-orbits/STF295-orbit.jpg

Robert Zebahl
102mm f/11, 160x
Quite easy at a moderate distance, whereby the companion appeared rather faint and was best visible with averted vision.
152mm f/5.9, 129x
Easy. The quite dim companion is immediately visible in moderate distance clearly outside of the first diffraction ring despite few, high clouds. The primary component appeared white-yellowish.

STF 301 (**)

Name: STF301
Type: **
Constellation: Per
Coordinates: 02h47m38.75s / +53°56'35.80"

Components:
m1 m2 ρ θ Year
7m8 8m7 8.2" 18° 2016
Robert Zebahl
70mm f/5.7, 22x, Bortle 6
Rather faint double star with a handful of other stars in the immediate vicinity. At 22x clearly separated, but still close together with visible difference in brightness. At 31x the primary component looked slightly orange.

STF 311 (**)

Name: STF311, pi Ari, 42 Ari
Type: **
Constellation: Ari
Coordinates: 02h49m17.55s / +17°27'51.50"

Components:
m1 m2 ρ θ Year
AB 5m3 8m0 3.3" 118° 2015
Robert Zebahl
70mm f/5.7, 133x
The companion is visible as elongated, non-condensed brightening in the first diffraction ring of the primary component.

STF 331 (**)

Name: STF331
Type: **
Constellation: Per
Coordinates: 03h00m52.18s / +52°21'06.50"

Components:
m1 m2 ρ θ Year
5m2 6m2 11.8" 86° 2018
Robert Zebahl
63mm f/13.3, 46x
Easy to separate with relatively large difference in brightness.

STF 360 (**)

Name: STF360
Type: **
Constellation: Per
Coordinates: 03h12m09.59s / +37°13'03.30"

Components:
m1 m2 ρ θ Year
8m0 8m3 2.7" 126° 2015

../images/binary-star-orbits/STF360-orbit.jpg

Robert Zebahl
70mm f/5.7, 67x, Bortle 6
Pretty faint double star. At 57x barely separable with almost touching diffraction disks. The components seemed similarly bright. At 67x still very close together, at 100x easy to separate.
152mm f/5.9, 69x, Bortle 6-, SQM-L 19.0
Split, but close together, similarly bright. The double star appears overall slightly orange compared to the surrounding stars.

STF 369 (**)

Name: STF369
Type: **
Constellation: Per
Coordinates: 03h17m11.45s / +40°28'58.60"

Components:
m1 m2 ρ θ Year
6m8 7m7 3.6" 29° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 6
At 44x still separable with noticeable difference in brightness. At 57x well separable, whereby the components are still very close together. The difference in brightness is more clearly visible here.

152mm f/5.9, 100x, Bortle 6-, SQM-L 19.0
Easily separable with clear difference in brightness. In terms of color, both components appeared slightly different: white-yellowish, slightly orange.

STF 389 (**)

Name: STF389
Type: **
Constellation: Cam
Coordinates: 03h30m10.93s / +59°21'57.80"

Components:
m1 m2 ρ θ Year
AB 6m4 7m9 2.6" 72° 2018
Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.2
Easy to find and separated at 67x, but very tight. Easily separable at 133x, still relatively tight together with significant difference in brightness.

STF 391 (**)

Name: STF391
Type: **
Constellation: Per
Coordinates: 03h29m13.74s / +45°02'57.50"

Components:
m1 m2 ρ θ Year
7m6 8m3 3.9" 96° 2018
Robert Zebahl
70mm f/5.7, 57x, Bortle 6
Clearly split, but close together, moderate difference in brightness. The double star is located in a very beautiful star field with some of the stars appearing colored, but this only came into its own at low magnification.

152mm f/5.9, 69x, Bortle 6-, SQM-L 19.0
Easy to separate with moderate difference in brightness. Slight difference in color: white-yellowish, slightly orange.

STF 401 (**)

Name: STF401
Type: **
Constellation: Tau
Coordinates: 03h31m20.76s / +27°34'18.50"

Components:
m1 m2 ρ θ Year
AB 6m6 6m9 11.5" 270° 2018
Robert Zebahl
120mm f/5, 18x, Bortle 6-, NELM 4m8+, SQM-L 19.1
Barely split at 18x. At 40x difference in brightness is visible. Nice view together with the double star STFA7 located northwest.

STF 419 (**)

Name: STF419
Type: **
Constellation: Cam
Coordinates: 03h42m45.19s / +69°50'44.30"

Components:
m1 m2 ρ θ Year
AB 7m8 7m8 2.9" 73° 2018
Robert Zebahl
70mm f/5.7, 67x, Bortle 6, SQM-L 19.2
Separated, but tight with equally bright components. Beautiful sight.

STF 425 (**)

Name: STF425
Type: **
Constellation: Per
Coordinates: 03h40m07.24s / +34°06'59.30"

Components:
m1 m2 ρ θ Year
AB 7m5 7m6 1.9" 59° 2018

../images/binary-star-orbits/STF425-AB-orbit.jpg

Robert Zebahl
152mm f/5.9, 129x, Bortle 6, SQM-L 19.2
Beautifully separated, relatively close together, very little difference in brightness.

STF 427 (**)

Name: STF427, V1268 Tau
Type: **
Constellation: Tau
Coordinates: 03h40m38.77s / +28°46'24.00"

Components:
m1 m2 ρ θ Year
7m4 7m8 7.0" 207° 2016
Robert Zebahl
120mm f/5, 40x, Bortle 6-, NELM 4m8+, SQM-L 19.1
At 40x barely split. At 75x easily split with visible difference in brightness.

STF 464 (**)

Name: STF464, zeta Per, 44 Per
Type: **
Constellation: Per
Coordinates: 03h54m07.92s / +31°53'01.20"

Components:
m1 m2 ρ θ Year
AB 2m9 9m2 12.9" 209° 2012
AC 2m9 11m2 33.3" 286° 2012
AD 2m9 10m4 98.6" 195° 2012
AE 2m9 10m0 120.0" 186° 2012
Robert Zebahl
102mm f/11, 106x, Bortle 4, SQM-L 21.2
AB: Easy to separate, but the B component appeared only as a very faint, tiny companion.

STF 470 (**)

Name: STF470, 32 Eri
Type: **
Constellation: Eri
Coordinates: 03h54m17.49s / -02°57'17.00"

Components:
m1 m2 ρ θ Year
AB 4m8 5m9 6.9" 349° 2018
Robert Zebahl
55mm f/9.1, 27x, Bortle 6, NELM 5m0+
At 27x split, but still tight with noticeable difference in brightness. A slight difference in colors could be seen. At 56x the color difference was very evident: The brighter component appeared slightly yellowish, the fainter one slightly bluish. Highly recommended! The sketch was done few days later during another observation.

../sketches/2019-02-09_32_eri.jpg

STF 471 (**)

Name: STF471, epsilon Per, 45 Per
Type: **
Constellation: Per
Coordinates: 03h57m51.22s / +40°00'36.90"

Components:
m1 m2 ρ θ Year
AB 2m9 8m9 9.1" 10° 2015
Robert Zebahl
63mm f/13.3, 46x
Easy to separate, but much fainter, second component, which appears as a small, faint spot. Nice view.

STF 479 (**)

Name: STF479
Type: **
Constellation: Tau
Coordinates: 04h00m56.81s / +23°12'05.40"

Components:
m1 m2 ρ θ Year
AB 6m9 7m8 7.5" 127° 2018
AC 6m9 9m4 57.7" 243° 2018
Robert Zebahl
102mm f/11, 28x, Bortle 6, SQM-L 19.3, Seeing 2/5
Components A & B clearly separated with visible difference in brightness. Noticeably fainter component C much wider apart. All three components form an obtuse triangle.

152mm f/5.9, 49x, Bortle 6, SQM-L 19.3, Seeing 2/5
Nice view. All three components easy to separate. A: white-yellowish; B: creamy white.

8" f/6, 37x, Bortle 4, SQM-L 21.00
AB: Nice, evident double star, easy to split. Slight difference in brightness.

STF 494 (**)

Name: STF494
Type: **
Constellation: Tau
Coordinates: 04h08m53.50s / +23°05'55.10"

Components:
m1 m2 ρ θ Year
7m5 7m7 5.3" 188° 2018
Robert Zebahl
102mm f/11, 62x, Bortle 6, SQM-L 19.3, Seeing 2/5
At 28x separated, but very tight, similarly bright, both whitish. At 62x easy to separate, little difference in brightness and color: slightly orange; white-bluish. Color impression slightly more intense at 86x.

152mm f/5.9, 49x, Bortle 6, SQM-L 19.3, Seeing 2/5
Easy to separate at 49x with subtle color differences: slightly orange; white-bluish. Color impression slightly more intense at 100x. Beautiful sight.

STF 559 (**)

Name: STF559
Type: **
Constellation: Tau
Coordinates: 04h33m33.04s / +18°01'00.20"

Components:
m1 m2 ρ θ Year
7m0 7m0 3.0" 277° 2018
Robert Zebahl
70mm f/5.7, 57x
Barely split with similarly bright components.

102mm f/11, 160x
Very nice view! Easy to separate, similarly bright at a nice distance from each other. The colors of the components changed over time: orange and subtle blue.

152mm f/5.9, 69x
Beautiful sight, similar bright components, pretty tight.

STF 572 (**)

Name: STF572
Type: **
Constellation: Tau
Coordinates: 04h38m29.58s / +26°56'25.60"

Components:
m1 m2 ρ θ Year
AB 7m4 7m2 4.4" 189° 2018

../images/binary-star-orbits/STF572-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x
Clearly separated, easy with beautiful color contrast: A slightly orange, B white.

STF 616 (**)

Name: STF616, omega Aur, 4 Aur
Type: **
Constellation: Aur
Coordinates: 04h59m15.41s / +37°53'24.90"

Components:
m1 m2 ρ θ Year
AB 5m0 8m2 4.7" 2015
Robert Zebahl
70mm f/5.7, 57x
Easy, still relatively tight with a large difference in brightness. Component A appeared pretty bright and white-yellowish, while B appeared only as a tiny star. Very nice sight.

STF 644 (**)

Name: STF644
Type: **
Constellation: Aur
Coordinates: 05h10m18.81s / +37°18'06.70"

Components:
m1 m2 ρ θ Year
AB 7m0 6m8 1.6" 221° 2019
Robert Zebahl
70mm f/5.7, 100x
At 57x slightly elongated with a partially visible notching. At 100x & 133x two clearly overlapping diffraction disks are visible as figure '8' with a small difference in brightness.

102mm f/11, 129x
Grand sight! Two almost touching diffraction disks, slight difference in brightness, both slightly yellowish.

152mm f/5.9, 129x
Great view, easy to separate, but still quite close together with low difference in brightness. Both components appeared slightly orange.

STF 648 (**)

Name: STF648
Type: **
Constellation: Aur
Coordinates: 05h10m59.19s / +32°02'19.50"

Components:
m1 m2 ρ θ Year
AB 8m1 8m9 4.7" 62° 2019

../images/binary-star-orbits/STF648-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 40x, Bortle 6, SQM-L 19.4
At 40x tight with obviously fainter component.
70mm f/5.7, 33x
Separated, but tight with noticeable difference in brightness.

STF 664 (**)

Name: STF664
Type: **
Constellation: Ori
Coordinates: 05h15m10.54s / +08°25'56.80"

Components:
m1 m2 ρ θ Year
7m8 8m4 4.8" 177° 2019
Robert Zebahl
70mm f/5.7, 100x, Bortle 6, SQM-L 19.2
At 44x barely split. At 100x easily split with obvious difference in brightness.

STF 666 (**)

Name: STF666
Type: **
Constellation: Aur
Coordinates: 05h17m05.80s / +33°19'47.20"

Components:
m1 m2 ρ θ Year
7m8 7m9 3.2" 75° 2019
Robert Zebahl
55mm f/9.1, 83x, Bortle 6, SQM-L 19.4
At 40x slightly elongated, at 38x separated, but tight. Overall faint with components of similar brightness.

70mm f/5.7, 57x
Split, no difference in brightness and color. Very nice!

STF 668 (**)

Name: STF668, 19 Ori, beta Ori, Rigel
Type: **
Constellation: Ori
Coordinates: 05h14m32.27s / -08°12'05.90"

Components:
m1 m2 ρ θ Year
A-BC 0m3 6m8 9.7" 202° 2017
Robert Zebahl
55mm f/9.1, 83x
The second component was immediately seen as faint companion.

../sketches/2019-01-21_stf668.jpg

70mm f/5.7, 67x
First attempt at 133x: much fainter component clearly visible as a tiny star at a relatively large distance. After that the visibility was easy even at 67x. At 44x the faint component could only be guessed.

102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3-4/5
Much fainter companion immediately visible as tiny star far outside the diffraction pattern of the primary component.

STF 669 (**)

Name: STF669
Type: **
Constellation: Aur
Coordinates: 05h18m56.78s / +45°14'51.40"

Components:
m1 m2 ρ θ Year
8m4 9m0 9.9" 278° 2015
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Well separated with visible difference in brightness.

STF 688 (**)

Name: STF688
Type: **
Constellation: Ori
Coordinates: 05h19m20.88s / -10°44'49.90"

Components:
m1 m2 ρ θ Year
7m5 7m5 10.7" 95° 2015
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.2
Clearly split with decent angular distance. Components appeared nearly equally bright.

STF 698 (**)

Name: STF698
Type: **
Constellation: Aur
Coordinates: 05h25m12.94s / +34°51'18.60"

Components:
m1 m2 ρ θ Year
AB 6m7 8m3 31.3" 348° 2018
Robert Zebahl
102mm f/11, 62x, Seeing 2-3/5
Beautiful double star, easy to separate and quite striking. Primary component appeared in clear orange, the companion was too faint to identify the color.

152mm f/5.9, 22x, Seeing 2-3/5
Easy with a attractive separation and a clear difference in brightness. A: pale yellow; B: creamy white with a touch of blue. At 49x the color impression was a bit more intense. Located in beautiful field of stars.

STF 699 (**)

Name: STF699
Type: **
Constellation: Aur
Coordinates: 05h25m38.50s / +38°02'41.10"

Components:
m1 m2 ρ θ Year
AB 7m9 8m6 8.9" 346° 2018
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Well separated with slightly fainter companion.

70mm f/5.7, 22x
Separated at 22x, but still a relatively tight pair with a moderate difference in brightness. Together with sigma Aur in one field of view. Overall rather dim double star. At 57x very nice view! A: pale orange, B: slightly bluish

STF 700 (**)

Name: STF700, V1804 Ori
Type: **
Constellation: Ori
Coordinates: 05h23m05.54s / +01°03'24.70"

Components:
m1 m2 ρ θ Year
7m7 7m9 4.8" 2017
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.2
At 44x split, but very close together. At 100x clearly split with nearly equally bright components.

STF 716 (**)

Name: STF716, 118 Tau
Type: **
Constellation: Tau
Coordinates: 05h29m16.49s / +25°09'01.10"

Components:
m1 m2 ρ θ Year
AB 5m8 6m7 4.9" 209° 2019
Robert Zebahl
70mm f/5.7, 33x
At 33x very tight with visible difference in brightness. At 47x very nice view. Both components appeared white.

STF 718 (**)

Name: STF718
Type: **
Constellation: Aur
Coordinates: 05h32m20.59s / +49°23'36.50"

Components:
m1 m2 ρ θ Year
AB 7m5 7m5 7.7" 73° 2015
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Easy to split with similarly bright components. Nive view.

STF 719 (**)

Name: STF719
Type: **
Constellation: Aur
Coordinates: 05h30m06.14s / +29°32'55.30"

Components:
m1 m2 ρ θ Year
AB 7m5 8m8 1.4" 336° 2016
AC 7m5 9m4 15.2" 353° 2016
Robert Zebahl
70mm f/5.7, 22x
AC: At 22x clearly visible difference in brightness at moderate separation. The companion appears only as a dim star. At 57x the color contrast is also quite noticeable. A: light orange, C: silvery blue

102mm f/11, 62x, Seeing 2-3/5
AC: Easy with a rather dim companion. The color seemed a bit more intense than in the 6-inch refractor. A: lovely pale orange; B: grey-bluish.

152mm f/5.9, 129x, Bortle 5, SQM-L 20.7, Seeing 3/5
AB: At 129x clearly elongated. Difference in brightness visible. The seeing was mediocre (3/5), so that the diffraction disks were only occasionally visible. At 180x no better.

152mm f/5.9, 49x, Seeing 2-3/5
AC: Easy to separate with a significant difference in brightness. A appeared in bright orange, B appeared greyish-blue.

STF 730 (**)

Name: STF730
Type: **
Constellation: Tau
Coordinates: 05h32m14.14s / +17°03'29.30"

Components:
m1 m2 ρ θ Year
AB 6m1 6m4 9.7" 142° 2018
Robert Zebahl
70mm f/5.7, 22x
At 22x beautiful sight, easy to separate with little difference in brightness. A appeared slightly yellowish. At 57x moderate, but still very nice color contrast: A yellowish, B rather white.

STF 736 (**)

Name: STF736
Type: **
Constellation: Aur
Coordinates: 05h37m07.20s / +41°49'41.70"

Components:
m1 m2 ρ θ Year
7m5 8m6 2.7" - 2019
Robert Zebahl
70mm f/5.7, 57x
At 57x split with almost no space in between. At 100x clearly split with noticeable fainter component.

STF 742 (**)

Name: STF742
Type: **
Constellation: Tau
Coordinates: 05h36m26.38s / +21°59'35.10"

Components:
m1 m2 ρ θ Year
7m1 7m5 4.2" 275° 2019
Located about 0.5 degree east of Messier 1.

../images/binary-star-orbits/STF742-orbit.jpg

Robert Zebahl
102mm f/11, 62x, Bortle 6, SQM-L 19.3, Seeing 2/5
Beautifully separated, relatively tight with well visible difference in brightness. Points directly toward Messier 1 and can be observed with it in one field of view. Very nice!

120mm f/5, 48x, Bortle 6, SQM-L 19.2
Nice, evident double near Messier 1. Easy to split with almost equally bright components.

152mm f/5.9, 69x, Bortle 6, SQM-L 19.3, Seeing 2/5
At 49x just so, at 69x easily separable. The fainter component appeared a little warmer in terms of color. Great view together with Messier 1 in the field of view.

8" f/6, 80x, Bortle 4-, SQM-L 20.8
Nice double star with nearly equally bright components.

STF 749 (**)

Name: STF749
Type: **
Constellation: Tau
Coordinates: 05h37m08.84s / +26°55'28.30"

Components:
m1 m2 ρ θ Year
AB 6m5 6m5 1.1" 319° 2017
AC 6m5 10m5 181.6" 299° 2011

../images/binary-star-orbits/STF749-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x
AB: I had the impression that in the correct position angle, without knowing that angle during observation, a minimal elongation could be detected. But observation is borderline and too doubtful.

STF 764 (**)

Name: STF764
Type: **
Constellation: Aur
Coordinates: 05h41m20.98s / +29°29'14.70"

Components:
m1 m2 ρ θ Year
6m4 7m1 25.6" 14° 2017
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Easy to split with large distance and noticeable difference in brightness.

70mm f/5.7, 22x
Very easy and bright, pretty wide apart with a small difference in brightness; whitish and slightly yellowish. A nice double star for binoculars.

STF 774 (**)

Name: STF774, zeta Ori, 50 Ori, Alnitak
Type: **
Constellation: Ori
Coordinates: 05h40m45.52s / -01°56'33.30"

Components:
m1 m2 ρ θ Year
AB 1m9 3m7 2.4" 167° 2017
AC 1m9 9m6 58.5" 10° 2017

../images/binary-star-orbits/STF774-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 128x, Bortle 6
AB: Big difference in brightness. I could see the fainter component near the first ring of the Airy pattern of the brighter component.

STF 796 (**)

Name: STF796
Type: **
Constellation: Aur
Coordinates: 05h49m55.53s / +31°47'08.70"

Components:
m1 m2 ρ θ Year
AB 7m2 8m2 3.7" 62° 2019
Robert Zebahl
55mm f/9.1, 83x, Bortle 6, SQM-L 19.4
Well split with noticeable fainter companion.

STF 845 (**)

Name: STF845, 41 Aur
Type: **
Constellation: Aur
Coordinates: 06h11m36.59s / +48°42'39.60"

Components:
m1 m2 ρ θ Year
6m2 6m9 7.6" 357° 2018
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Relatively tight with visible difference in brightness.

STF 848 (**)

Name: STF848
Type: **
Constellation: Ori
Coordinates: 06h08m30.36s / +13°58'15.80"

Components:
m1 m2 ρ θ Year
AB 7m3 8m2 2.6" 110° 2019
Robert Zebahl
70mm f/5.7, 100x, Bortle 6, SQM-L 19.2
Well split with obvious difference in brightness.

STF 872 (**)

Name: STF872
Type: **
Constellation: Aur
Coordinates: 06h15m39.06s / +36°08'55.30"

Components:
m1 m2 ρ θ Year
AB 6m9 7m4 11.3" 215° 2017
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Well separated with significant difference in brightness.

STF 877 (**)

Name: STF877
Type: **
Constellation: Ori
Coordinates: 06h14m42.67s / +14°35'10.80"

Components:
m1 m2 ρ θ Year
7m5 8m0 5.7" 263° 2019
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.2
Well split, but close together. Little difference in brightness noticeable.

STF 899 (**)

Name: STF899
Type: **
Constellation: Gem
Coordinates: 06h22m49.64s / +17°34'27.30"

Components:
m1 m2 ρ θ Year
7m4 8m0 2.2" 17° 2019
Robert Zebahl
70mm f/5.7, 133x
Separated, but tight with visible difference in brightness.

STF 900 (**)

Name: STF900, epsilon Mon, 8 Mon
Type: **
Constellation: Mon
Coordinates: 06h23m46.10s / +04°35'34.20"

Components:
m1 m2 ρ θ Year
AB 4m4 6m6 12.0" 29° 2017
Robert Zebahl
55mm f/9.1, 42x
Relatively large distance and clear difference in brightness. The lighter component seemed white-yellowish, the weaker one slightly greenish-blue. The color contrast, however, was not particularly conspicuous.

STF 918 (**)

Name: STF918
Type: **
Constellation: Aur
Coordinates: 06h33m57.62s / +52°27'41.80"

Components:
m1 m2 ρ θ Year
AB 7m3 8m2 4.9" 336° 2019
Robert Zebahl
55mm f/9.1, 40x, Bortle 6, SQM-L 19.4
At 40x tight, at 55x well split with obviously fainter companion.

STF 924 (**)

Name: STF924, 20 Gem
Type: **
Constellation: Gem
Coordinates: 06h32m18.52s / +17°47'03.40"

Components:
m1 m2 ρ θ Year
AB 6m3 6m9 20.7" 212° 2017
BC 6m9 13m0 47.8" 144° 2014
Robert Zebahl
70mm f/5.7, 22x
AB: At 22x bright, immediately conspicuous, although in a relatively star-rich surrounding. Moderate but beautiful color contrast: bright orange, decent blue. Also at 44x very beautiful sight.

152mm f/5.9, 69x, Bortle 6, SQM-L 19.3, Seeing 3/5
AB: Easy, bright, moderately uneven. Nice contrast in color: slight orange, white-bluish.

STF 928 (**)

Name: STF928
Type: **
Constellation: Aur
Coordinates: 06h34m41.81s / +38°32'24.50"

Components:
m1 m2 ρ θ Year
AB 7m9 8m6 3.4" 131° 2019
AC 7m9 12m4 130.9" 124° 2002
BC 8m6 12m4 127.3" 124° 2015
Robert Zebahl
102mm f/11, 62x, Bortle 6
AB: At 28x the double star already appeared elongated, at 62x beautifully separated, with component A shining in a warm, decent orange. At 125x A appeared orange, B grey-bluish.

152mm f/5.9, 69x, Bortle 6, SQM-L 19.3, Seeing 3/5
AB: Clearly separated, but tight. Moderate difference in brightness. Nice view with the nearby double stars STT147 & STF 929 and the carbon star UU Aur!

STF 929 (**)

Name: STF929
Type: **
Constellation: Aur
Coordinates: 06h35m22.03s / +37°42'55.10"

Components:
m1 m2 ρ θ Year
7m3 8m4 6.5" 24° 2016
Robert Zebahl
152mm f/5.9, 69x, Bortle 6, SQM-L 19.3, Seeing 3/5
Easy to separate, clear difference in brightness, slight color contrast. Primary component showed a slight orange color, the color of the companion was not clearly defineable. Nice view with the nearby double stars STT147 & STF 928 and the carbon star UU Aur!

STF 932 (**)

Name: STF932
Type: **
Constellation: Gem
Coordinates: 06h34m21.57s / +14°45'08.30"

Components:
m1 m2 ρ θ Year
8m3 8m5 1.6" 305° 2017

../images/binary-star-orbits/STF932-orbit.jpg

Robert Zebahl
70mm f/5.7, 150x
Unfortunately a nearby lamp bothered me. I could see the double star at least elongated.

STF 941 (**)

Name: STF941
Type: **
Constellation: Aur
Coordinates: 06h38m40.76s / +41°34'53.40"

Components:
m1 m2 ρ θ Year
AB 7m2 8m2 2.0" 83° 2019
AC 7m2 10m5 83.9" 135° 2015
Robert Zebahl
102mm f/11, 86x, Bortle 6
AB: At 62x only visible as figure '8'. The difference in brightness is hardly noticeable. At 86x barely separated, obvious. Clearly separated at 125x, but still tight with a moderate brightness difference.

102mm f/11, 28x, Bortle 6
AC: Distant, faint companion that is less attracting attention. Used magnifications between 28x and 125x.

STF 946 (**)

Name: STF946
Type: **
Constellation: Lyn
Coordinates: 06h44m51.62s / +59°26'57.40"

Components:
m1 m2 ρ θ Year
7m3 9m1 4.0" 129° 2019
Robert Zebahl
102mm f/11, 86x, Bortle 6-, SQM-L 19.0
Easy to split with noticeable difference in brightness. Very nice view together with the triple system STF 948 in one field of view!

../sketches/2020-03-23_stf946_stf948.jpg

152mm f/5.9, 100x, Bortle 6, SQM-L 19.4
At 100x and 129x easy to separate, quite uneven. Primary component appeared yellowish, the fainter one rather greyish. Fantastic view together with 12 Lyn (STF 948) in one field of view!

STF 948 (**)

Name: STF948, 12 Lyn
Type: **
Constellation: Lyn
Coordinates: 06h46m14.15s / +59°26'30.10"

Components:
m1 m2 ρ θ Year
AB 5m4 6m0 1.9" 64° 2019
AC 5m4 7m0 8.8" 310° 2018

../images/binary-star-orbits/STF948-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 167x
AB: Components A and B separated, whereby the Airy disks slightly overlap. The difference in brightness was well visible.

../sketches/2019-01-21_stf948.jpg

55mm f/9.1, 27x
AC: Components A/B and C well separated, but tight. Significant difference in brightness. The fainter C companion appeared slightly orange, the brighter one white-bluish.

63mm f/13.3, 140x
AB: Components A and B split with almost no space in between. The difference in brightness was visible.

../sketches/2019-01-22_stf948.jpg

70mm f/5.7, 133x
AB: Both components A + B clearly split, whereby the diffraction rings where merged together. A very nice view together with component C. I sketched this triplet, which reflects my impression well. Unfortunately, the distance and position angle are not particularly well observed. Also the difference in brightness I didn't noticed during my observation.

../sketches/2019-01-20_stf948.jpg

70mm f/5.7, 22x
AC: Well split, relatively close together with significant difference in brightness.

102mm f/11, 129x, Bortle 6-, SQM-L 19.0
At 28x the pair AC is nicely separated without any problems. The close pair AB is already recognizable at 86x as a clear figure '8', at 125x wonderfully separated. The components A & B appear yellowish. Very nice view together with STF 946 in one field of view!

../sketches/2020-03-23_stf946_stf948.jpg

152mm f/5.9, 129x, Bortle 6, SQM-L 19.4
At 49x the pair AC is beautifully separated with a significant difference in brightness. At 100x, the close pair AB is also separated, although still very close together. A slight difference in brightness is noticeable. At 129x, the view is magnificent. The two bright components A & B present themselves yellowish, the fainter component C rather greyish. STF 948 can be well observed in a field of view with the neighbouring double star STF 946. Both show a nice overall scenery.

STF 957 (**)

Name: STF957
Type: **
Constellation: Gem
Coordinates: 06h45m10.02s / +30°49'33.50"

Components:
m1 m2 ρ θ Year
AB 7m5 9m4 3.8" 90° 2019
AC 7m5 13m8 19.3" 100° 2015
Robert Zebahl
70mm f/5.7, 100x
AB: Too faint for a separation. Primary component visible, companion not. Used magnifications from 67x to 133x. Observation from city at moon (83%).

152mm f/5.9, 129x, Bortle 6, SQM-L 19.3, Seeing 3/5
AB: Easy with significant difference in brightness and moderate angular distance.

STF 958 (**)

Name: STF958
Type: **
Constellation: Lyn
Coordinates: 06h48m12.29s / +55°42'15.10"

Components:
m1 m2 ρ θ Year
AB 6m3 6m3 4.5" 77° 2019

../images/binary-star-orbits/STF958-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 33x
Clearly split, equally bright, close together. Nice view.
102mm f/11, 62x, Bortle 6-, SQM-L 19.0
Very nicely split. Both components appear similarly bright and white-yellowish.

STF 974 (**)

Name: STF974, 59 Aur
Type: **
Constellation: Aur
Coordinates: 06h53m01.41s / +38°52'08.90"

Components:
m1 m2 ρ θ Year
AB 6m1 10m2 22.2" 224° 2015
BC 10m2 12m8 25.6" 219° 2015
Robert Zebahl
102mm f/11, 28x, Bortle 6
AB: Easy, moderate distance, pretty uneven. A appeared white-yellowish, B only as a tiny star.

STF 982 (**)

Name: STF982, 38 Gem
Type: **
Constellation: Gem
Coordinates: 06h54m38.63s / +13°10'40.10"

Components:
m1 m2 ρ θ Year
AB 4m8 7m8 7.4" 143° 2018

../images/binary-star-orbits/STF982-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 27x
At 27x pretty tight with much fainter component. At 71x clearly separated with clear difference in brightness. Brighter component appeared slightly yellowish, the weaker one slightly bluish.
70mm f/5.7, 33x
Easy to separated with noticeable difference in brightness. The fainter component appeared slightly orange, the brighter one rather white.

STF 994 (**)

Name: STF994
Type: **
Constellation: Aur
Coordinates: 06h59m27.19s / +37°05'53.50"

Components:
m1 m2 ρ θ Year
AB 7m9 8m1 26.4" 55° 2017
Robert Zebahl
55mm f/9.1, 25x, Bortle 6, SQM-L 19.4
Well separated, large distance, slight difference in brightness.

STF 1001 (**)

Name: STF1001
Type: **
Constellation: Lyn
Coordinates: 07h03m05.51s / +54°10'26.60"

Components:
m1 m2 ρ θ Year
AB 7m8 9m4 9.1" 66° 2019
AC 7m8 9m3 9.9" 58° 2019
BC 9m4 9m3 1.6" 2019
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
2020-03-23: At 28x the pair A-BC is easy to separate. At 160x, the very close pair BC shows split. The component A appears slightly orange.

152mm f/5.9, 129x, Bortle 6, SQM-L 19.4
2020-03-23: At 22x, the wide pair A-BC already appears separated, but still very tight. At 69x, A appears in a decent orange. The pair BC shows elongated and rather greenish-bluish. At 100x BC is already visible as figure '8' and almost separated, at 129x clearly separated. Components B and C are still very close together and equally bright. The color impression remains. An interesting and rewarding triple system!

../sketches/2020-03-23_stf1001.jpg

STF 1007 (**)

Name: STF1007
Type: **
Constellation: Gem
Coordinates: 07h00m37.12s / +12°43'24.20"

Components:
m1 m2 ρ θ Year
AB 7m4 11m4 14.6" 300° 2015
AC 7m4 10m0 21.9" 244° 2015
AD 7m4 7m7 67.7" 28° 2016
Robert Zebahl
70mm f/5.7, 22x, Bortle 6
AD: Wide separation, small difference in brightness. Slight difference in color, but difficult to describe. Component A at least seemed rather white. South of STF1007 there is also the double star HJ3288 and the star HD52976, which appears in a bright orange. Together in one field of view a beautiful sight.

../sketches/2019-12-18_stf1007_hj3288.jpg

STF 1009 (**)

Name: STF1009
Type: **
Constellation: Lyn
Coordinates: 07h05m39.83s / +52°45'31.30"

Components:
m1 m2 ρ θ Year
AB 6m9 7m0 4.4" 148° 2019
Robert Zebahl
70mm f/5.7, 33x
Very nice view. Equally bright components, tight.

STF 1033 (**)

Name: STF1033
Type: **
Constellation: Lyn
Coordinates: 07h14m48.05s / +52°32'44.10"

Components:
m1 m2 ρ θ Year
AB 7m8 8m4 1.5" 278° 2017
AC 7m8 10m2 79.6" 273° 2015
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
The pair AB appears clearly separated, but still pretty tight with a well visible difference in brightness. The faint C component is wide apart at a similar position angle.

../sketches/2020-03-23_stf1033.jpg

STF 1050 (**)

Name: STF1050
Type: **
Constellation: Lyn
Coordinates: 07h19m51.29s / +54°55'18.40"

Components:
m1 m2 ρ θ Year
AB 8m1 8m8 19.3" 21° 2017
Robert Zebahl
70mm f/5.7, 22x
Rather faint, obviously split with visible difference in brightness. View similar to STF 1062.

102mm f/11, 28x, Bortle 6-, SQM-L 19.0

../sketches/2020-03-23_stf1050_stf1062.jpg

STF 1062 (**)

Name: STF1062, 19 Lyn
Type: **
Constellation: Lyn
Coordinates: 07h22m52.06s / +55°16'53.30"

Components:
m1 m2 ρ θ Year
AB 5m8 6m7 14.8" 316° 2018
Robert Zebahl
70mm f/5.7, 22x
Clearly separated, moderate distance, noticeable difference in brightness. The colors seemed different, but not exactly definable.

102mm f/11, 28x, Bortle 6-, SQM-L 19.0

../sketches/2020-03-23_stf1050_stf1062.jpg

152mm f/5.9, 22x, Bortle 6, SQM-L 19.4
Easy to separate, but still quite close together with visible difference in brightness. Colorwise unremarkable.

STF 1065 (**)

Name: STF1065, 20 Lyn
Type: **
Constellation: Lyn
Coordinates: 07h22m15.11s / +50°08'55.70"

Components:
m1 m2 ρ θ Year
7m5 7m7 14.9" 256° 2017
Robert Zebahl
70mm f/5.7, 22x
Nicely split, moderate distance, similarly bright.

STF 1066 (**)

Name: STF1066, delta Gem, 55 Gem
Type: **
Constellation: Gem
Coordinates: 07h20m07.39s / +21°58'56.40"

Components:
m1 m2 ρ θ Year
3m5 8m2 5.4" 234° 2017

../images/binary-star-orbits/STF1066-orbit.jpg

Robert Zebahl
55mm f/9.1, 71x
Large difference in brightness. The fainter component was well separated, but just a very tiny star.
102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3-4/5
Easy to separate with relatively large distance. The companion appeared as a tiny, faint star.

STF 1081 (**)

Name: STF1081
Type: **
Constellation: Gem
Coordinates: 07h24m08.94s / +21°27'28.00"

Components:
m1 m2 ρ θ Year
AB 7m7 8m5 1.9" 234° 2019
AC 7m7 9m9 107.0" 63° 2015
Robert Zebahl
102mm f/11, 86x, Bortle 6
AB: At 86x just separated, very close together with moderate difference in brightness. In relation to A, the components B & C are almost opposite each other. At 125x, A & B are easy to split.

102mm f/11, 28x, Bortle 6
AC: Rather wide apart from component A with noticeable difference in brightness. Less conspicuous.

STF 1083 (**)

Name: STF1083
Type: **
Constellation: Gem
Coordinates: 07h25m35.30s / +20°29'42.60"

Components:
m1 m2 ρ θ Year
7m3 8m1 6.8" 45° 2015
Robert Zebahl
70mm f/5.7, 22x
Unequal pair. At 22x very tight, at 44x well split. Fainter companion appeared slightly orange, brighter one white-bluish.

STF 1094 (**)

Name: STF1094
Type: **
Constellation: Gem
Coordinates: 07h27m25.99s / +15°18'59.00"

Components:
m1 m2 ρ θ Year
7m6 8m5 2.5" 97° 2019
Robert Zebahl
70mm f/5.7, 57x
At 57x barely split with noticeable difference in brightness. At 100x well split, but still tight.

STF 1110 (**)

Name: STF1110, alpha Gem, 66 Gem, Castor
Type: **
Constellation: Gem
Coordinates: 07h34m35.86s / +31°53'17.80"

Components:
m1 m2 ρ θ Year
AB 1m9 3m0 5.4" 53° 2019
AC 1m9 9m8 69.8" 163° 2017
AD 1m9 10m1 179.8" 221° 2017

../images/binary-star-orbits/STF1110-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 27x
AB: At 27x slight difference in brightness visible. Double star appeared as '8'. At 38x clearly split, but tight.
70mm f/5.7, 44x, Bortle 6
AB: At 44x the double star appeared as an '8'. At 100x clearly split with noticeable difference in brightness. Both components appeared white.

STF 1140 (**)

Name: STF1140
Type: **
Constellation: Gem
Coordinates: 07h48m22.61s / +18°20'12.40"

Components:
m1 m2 ρ θ Year
7m0 8m7 6.4" 273° 2015
Robert Zebahl
70mm f/5.7, 44x
Easy to separate with quite clear difference in brightness.

STF 1171 (**)

Name: STF1171
Type: **
Constellation: Cnc
Coordinates: 08h01m00.78s / +23°34'59.20"

Components:
m1 m2 ρ θ Year
6m5 9m9 2.0" 326° 2015
Robert Zebahl
102mm f/11, 187x
Observation from the city at half moon. At magnifications between 187x and 280x I could see the very dim companion almost permanently near the first diffraction ring. But the diffraction ring itself was hardly visible. Main problem here was probably the low brightness of the companion.

STF 1177 (**)

Name: STF1177, 17 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h05m37.06s / +27°31'46.90"

Components:
m1 m2 ρ θ Year
6m7 7m4 3.6" 350° 2019
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
Easy to separate, but still relatively close together. Well visible difference in brightness. Color of the components was not clearly visible. Nice view overall.

STF 1187 (**)

Name: STF1187
Type: **
Constellation: Cnc
Coordinates: 08h09m30.45s / +32°13'18.80"

Components:
m1 m2 ρ θ Year
AB 7m2 8m0 3.1" 20° 2019

../images/binary-star-orbits/STF1187-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
Split. Components very tight with noticeable difference in brightness.

STF 1196 & HUT1 (**)

Name: STF1196 & HUT1, zeta Cnc, 16 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h12m12.79s / +17°38'51.20"

Components:
m1 m2 ρ θ Year
STF1196 AC 5m3 5m8 6.3" 51° 2019
STF1196 AB-C 4m9 5m8 6.0" 64° 2018
STF1196 AB 5m3 6m2 1.1" 2018
HUT1 Ca-Cb 6m2 7m1 0.3" 233° 2018

../images/binary-star-orbits/STF1196-AB-C-orbit.jpg ../images/binary-star-orbits/STF1196-AB-orbit.jpg ../images/binary-star-orbits/HUT1-Ca-Cb-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6-
The wide pair AB-C is already separable at 22x. The pair AB shows at 133x two clearly overlapping diffraction disks with small difference in brightness, but without any notch.

../sketches/2020-03-24_stf1196.jpg

102mm f/11, 86x, Bortle 6-, SQM-L 19.2
AB-C: Easy to separate. A: light grey, B: pale orange.

120mm f/5, 67x, Bortle 6, SQM-L 19.3
AB-C: Evident difference in brightness, easy to split. Both components of similar color.
120mm f/5, 200x, Bortle 6, SQM-L 19.3
AB: Very tight. The Airy disks were still touching. Slight difference in brightness. Extremely beautiful triple star!

../sketches/2019-02-24_stf1196.jpg

STF 1245 (**)

Name: STF1245
Type: **
Constellation: Cnc
Coordinates: 08h35m51.05s / +06°37'13.90"

Components:
m1 m2 ρ θ Year
AB 6m0 7m2 10.1" 25° 2018
AC 6m0 10m7 100.4" 109° 2017
AD 6m0 11m9 110.3" 292° 2017
AE 6m0 9m6 114.8" 207° 2017
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
AB at 22x separated, but very close, uneven pair. A appeared white-yellowish, B orange, partly reddish. Opposite in a wide separation the fainter component E was visible. At 57x, A appeared white-yellowish, B orange.

../sketches/2020-03-24_stf1245.jpg

STF 1258 (**)

Name: STF1258
Type: **
Constellation: UMa
Coordinates: 08h43m25.41s / +48°51'41.90"

Components:
m1 m2 ρ θ Year
7m7 7m9 10.0" 330° 2017
Robert Zebahl
70mm f/5.7, 22x, Seeing 3/5
Easy to separate at 22x, similarly bright components at moderate distance. At 57x very small difference in brightness noticeable. The components appeared slightly orange and white-bluish, with the color changing from one component to another. A very strange effect, which I observed several times.

STF 1268 (**)

Name: STF1268, iota Cnc, 48 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h46m41.82s / +28°45'35.60"

Components:
m1 m2 ρ θ Year
4m1 6m0 30.7" 308° 2018
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.4
Striking, widely separated with noticeable difference in brightness. Moderate but beautiful color contrast: white-yellowish and grey-bluish.

102mm f/11, 28x
Grand sight! Pretty wide apart and unequal. A: decent orange, B: very nice light blue.

STF 1275 (**)

Name: STF1275
Type: **
Constellation: UMa
Coordinates: 08h51m26.19s / +57°31'38.10"

Components:
m1 m2 ρ θ Year
AB 8m7 8m9 1.9" 198° 2019
Robert Zebahl
70mm f/5.7, 100x
At 100x and 150x not permanently split. Components very close together.

STF 1282 (**)

Name: STF1282
Type: **
Constellation: Lyn
Coordinates: 08h50m44.28s / +35°04'15.40"

Components:
m1 m2 ρ θ Year
AB 7m6 7m8 3.5" 279° 2019
Robert Zebahl
70mm f/5.7, 57x, Bortle 6, SQM-L 19.4
Clearly separated, but close together with very little difference in brightness. The double star forms an acute-angled triangle together with two other stars.

STF 1289 (**)

Name: STF1289
Type: **
Constellation: Lyn
Coordinates: 08h54m44.33s / +43°35'04.70"

Components:
m1 m2 ρ θ Year
8m2 8m9 3.7" 2019
Robert Zebahl
70mm f/5.7, 57x, Bortle 6, SQM-L 19.4
Quite faint double star, but easy to separate with a noticeable difference in brightness and close components.

STF 1291 (**)

Name: STF1291, 57 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h54m14.65s / +30°34'45.80"

Components:
m1 m2 ρ θ Year
AB 6m1 6m4 1.6" 309° 2019
AB-C 5m5 9m2 54.6" 204° 2015

../images/binary-star-orbits/STF1291-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.4
AB: Immediately apparent as a double star. Diffraction disks overlapping slightly ('8'). Difference in brightness visible.

STF 1294 & SIN41 (**)

Name: STF1294 & SIN41
Type: **
Constellation: Cnc
Coordinates: 08h57m17.08s / +32°53'57.90"

Components:
m1 m2 ρ θ Year
STF1294 AB 9m0 10m8 15.6" 340° 2015
SIN41 AC 9m0 12m6 191.3" 285° 2015
Robert Zebahl
102mm f/11, 28x, Bortle 6-, SQM-L 19.0
STF1294 (AB): At 28x relatively widely separated and rather less striking near the bright star sigma 2 Cnc. Component A appeared slightly orange, the companion only as a dim star. Similar view at 86x.

STF 1296 (**)

Name: STF1296
Type: **
Constellation: Lyn
Coordinates: 08h59m16.74s / +34°56'46.90"

Components:
m1 m2 ρ θ Year
9m1 9m9 1.9" 76° 2019
Robert Zebahl
102mm f/11, 160x, Bortle 6-, SQM-L 19.0
Overall quite faint double star, but clearly separated with a moderate difference in brightness. Both components are still pretty close together.

STF 1298 (**)

Name: STF1298, 66 Cnc
Type: **
Constellation: Cnc
Coordinates: 09h01m24.13s / +32°15'08.30"

Components:
m1 m2 ρ θ Year
AB 6m0 8m6 4.4" 137° 2017
AC 6m0 12m0 187.6" 318° 2015
Robert Zebahl
70mm f/5.7, 80x, Bortle 6, SQM-L 19.4
AB: At 67x and 80x the companion is visible as a very faint star close to the main component. At 133x it is only visible as a slightly blurred tiny star just outside the first diffraction ring of the primary component.

102mm f/11, 62x, Bortle 6-, SQM-L 19.0
AB: At 62x clearly separated, significant difference in brightness. The companion can be seen well as a faint little star, apart from the primary component. At 125x easy to split. Component A appeared rather white.

STF 1306 (**)

Name: STF1306, sigma 2 UMa, 13 UMa
Type: **
Constellation: UMa
Coordinates: 09h10m23.53s / +67°08'03.30"

Components:
m1 m2 ρ θ Year
AB 4m9 8m8 4.3" 348° 2016
AC 4m9 10m3 197.8" 148° 2003

../images/binary-star-orbits/STF1306-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 100x, Seeing 3/5
AB: Companion almost permanently visible as elongated, non-condensed brightening of the first diffraction ring of the primary component at the correct position angle.

STF 1315 (**)

Name: STF1315
Type: **
Constellation: UMa
Coordinates: 09h12m45.94s / +61°40'32.70"

Components:
m1 m2 ρ θ Year
7m3 7m7 24.9" 27° 2017
Robert Zebahl
70mm f/5.7, 22x, Seeing 3/5
Medium bright double star, easy to separate with attractive distance and slight difference in brightness. Together with 16 UMa in one field of view. The brighter component appeared slightly orange, the fainter one showed a hint of blue. However, the colors of the components changed over time. At 57x similar view.

STF 1318 (**)

Name: STF1318
Type: **
Constellation: UMa
Coordinates: 09h13m38.79s / +46°59'25.30"

Components:
m1 m2 ρ θ Year
7m8 9m5 2.4" 228° 2018
Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.4
Separated with clear difference in brightness. The faint companion is slightly outside the first diffraction ring of the primary component.

STF 1333 (**)

Name: STF1333
Type: **
Constellation: Lyn
Coordinates: 09h18m25.97s / +35°21'51.30"

Components:
m1 m2 ρ θ Year
6m6 6m7 1.9" 50° 2017
Robert Zebahl
63mm f/13.3, 120x
At 93x seen as '8', at 120x split, but pretty tight with no visible difference in brightness.

STF 1334 (**)

Name: STF1334, 38 Lyn
Type: **
Constellation: Lyn
Coordinates: 09h18m50.64s / +36°48'09.30"

Components:
m1 m2 ρ θ Year
AB 3m9 6m1 2.5" 229° 2017

../images/binary-star-orbits/STF1334-AB-orbit.jpg

Robert Zebahl
63mm f/13.3, 140x
Fainter companion only seen as permanent brightening on the first diffraction ring.

../sketches/2019-01-22_stf1334.jpg

STF 1344 (**)

Name: STF1344
Type: **
Constellation: LMi
Coordinates: 09h23m28.35s / +39°08'05.10"

Components:
m1 m2 ρ θ Year
9m0 9m5 3.8" 104° 2018
Robert Zebahl
120mm f/5, 75x, Bortle 7+, NELM 5m0, SQM-L 18.8
At 50x and 75x split, but tight with little difference in brightness.

STF 1350 (**)

Name: STF1350
Type: **
Constellation: UMa
Coordinates: 09h34m19.56s / +66°47'42.30"

Components:
m1 m2 ρ θ Year
AB 8m3 8m3 10.2" 249° 2015
AC 8m3 9m2 131.0" 216° 2015
Robert Zebahl
152mm f/5.9, 100x, Bortle 6-, SQM-L 19.1
At 22x, all three components are already visible, with A & B still standing quite close together. Component C is less prominent. At 69x and 100x, the pair AB shows a nice color contrast: The eastern component mostly appeared in a slightly shiny orange, while the other component appeared more white-bluish. During the observation, however, the colors changed between both components. At the time of observation, the pretty bright comet C/2019 Y4 Atlas was also in the same field of view - a great scene! Note to the sketch: The positions of the stars to each other do not exactly match, also the alignment of the pair AB to C.

../sketches/2020-03-18_stf1350_c2019_y4_atlas.jpg

STF 1374 (**)

Name: STF1374
Type: **
Constellation: LMi
Coordinates: 09h41m21.88s / +38°57'01.90"

Components:
m1 m2 ρ θ Year
AB 7m3 8m7 2.8" 311° 2017

../images/binary-star-orbits/STF1374-AB-orbit.jpg

Robert Zebahl
120mm f/5, 168x, Bortle 7+, NELM 5m0, SQM-L 18.8
At 50x elongated, at 75x seen as '8'. At 168x clearly split with obviously fainter component.

STF 1399 (**)

Name: STF1399
Type: **
Constellation: Leo
Coordinates: 09h57m02.21s / +19°45'44.60"

Components:
m1 m2 ρ θ Year
7m7 8m4 30.2" 176° 2017
Robert Zebahl
70mm f/5.7, 22x
Easy to split with nice distance and obviously unequal. A conspicuous group of fainter stars is nearby. Main component appeared in a warm-white, fainter somehow darker (partly bluish, partly slightly orange).

STF 1424 (**)

Name: STF1424, gamma Leo, 41 Leo, Algieba
Type: **
Constellation: Leo
Coordinates: 10h19m58.35s / +19°50'29.40"

Components:
m1 m2 ρ θ Year
AB 2m4 3m6 4.9" 126° 2019

../images/binary-star-orbits/STF1424-AB-orbit-solution-1.jpg ../images/binary-star-orbits/STF1424-AB-orbit-solution-2.jpg

Robert Zebahl
55mm f/9.1, 38x, Bortle 6-, SQM-L 19.1
At 38x split, but very tight with noticeable difference in brightness. At 56x and higher beautiful view of both components, which seemed to have similar colors.

../sketches/2019-02-09_gamma_leo.jpg

55mm f/9.1, 59x, Bortle 6, SQM-L 19.5
Very nice unequal double. A appeared yellow-orange, B rather white-bluish.

../sketches/2019-03-09_gamma_leo.jpg

70mm f/5.7, 100x, Bortle 6-
At 67x still a relatively close pair, but well separated with quite a clear difference in brightness. At 100x easy to separate and visible color difference: A yellowish to slightly orange, B white-yellowish.

102mm f/11, 125x, Bortle 7, SQM-L 18.8, Seeing 3/5
Very nicely separated with wonderful contrast in brightness and color. Primary component slightly orange, companion yellowish.
120mm f/5, 66x, Bortle 6-, SQM-L 19.1
At 48x easily seen as double star. It appeared as '8'. At 66x pretty tight with visible difference in brightness.

STF 1426 (**)

Name: STF1426
Type: **
Constellation: Leo
Coordinates: 10h20m32.32s / +06°25'47.60"

Components:
m1 m2 ρ θ Year
AB-C 7m3 9m4 7.6" 2018
AB 8m0 8m3 0.9" 313° 2018

../images/binary-star-orbits/STF1426-AB-orbit.jpg

Robert Zebahl
102mm f/11, 160x, Bortle 6-
AB-C: Quite large angular distance and therefor easy to separate. The C component was pretty faint.
102mm f/11, 160x, Bortle 6-
AB: At first glance elongated, on closer look visible as '8'.

STF 1431 (**)

Name: STF1431
Type: **
Constellation: Leo
Coordinates: 10h25m35.12s / +08°46'35.40"

Components:
m1 m2 ρ θ Year
7m8 9m1 3.6" 76° 2019
Robert Zebahl
70mm f/5.7, 67x
Separable at 67x, but very close together with a clear difference in brightness. Easy to separate at 100x. Next to it the star 44 Leo shines in a striking, bright orange.

STF 1443 (**)

Name: STF1443
Type: **
Constellation: LMi
Coordinates: 10h33m17.07s / +37°40'25.00"

Components:
m1 m2 ρ θ Year
9m9 10m0 5.3" 161° 2018
Robert Zebahl
120mm f/5, 50x, Bortle 7+, NELM 5m0, SQM-L 18.8
At 50x split with little distance. At 75x clearly split with small difference in brightness.

STF 1450 (**)

Name: STF1450, 49 Leo
Type: **
Constellation: Leo
Coordinates: 10h35m02.16s / +08°39'01.60"

Components:
m1 m2 ρ θ Year
5m8 7m9 2.2" 156° 2017
Robert Zebahl
70mm f/5.7, 133x
B component appeared as clear brightening on the first diffraction ring of the primary component in the correct position angle.

STF 1459 (**)

Name: STF1459
Type: **
Constellation: LMi
Coordinates: 10h40m12.46s / +38°24'11.40"

Components:
m1 m2 ρ θ Year
8m3 8m8 4.6" 153° 2019
Robert Zebahl
120mm f/5, 50x, Bortle 7+, NELM 5m0, SQM-L 18.8
Clearly split with noticeable difference in brightness.

STF 1466 (**)

Name: STF1466, 35 Sex
Type: **
Constellation: Sex
Coordinates: 10h43m20.91s / +04°44'51.60"

Components:
m1 m2 ρ θ Year
AB 6m2 7m1 6.9" 241° 2018
Robert Zebahl
102mm f/11, 28x, Bortle 6-, SQM-L 18.8
Very nice view. At 28x obviously unequal and easy to split. A appeared slightly orange. At 86x B appeared grey-blue.

../sketches/2019-04-06_35_sex.jpg

STF 1487 (**)

Name: STF1487, 54 Leo
Type: **
Constellation: Leo
Coordinates: 10h55m36.80s / +24°44'59.00"

Components:
m1 m2 ρ θ Year
4m5 6m3 6.8" 112° 2019
Robert Zebahl
55mm f/9.1, 27x
At 27x split, but very tight with noticeable difference in brightness. At 71x easy to separate. No visible color difference.

STF 1517 & BU1431 (**)

Name: STF1517 & BU1431, WDS11137+2008
Type: **
Constellation: Leo
Coordinates: 11h13m40.99s / +20°07'43.30"

Components:
m1 m2 ρ θ Year
STF1517 AB 7m5 8m0 0.7" 314° 2017
BU1431 AB-C 7m5 10m8 246.1" 97° 2015

../images/binary-star-orbits/STF1517-AB-orbit.jpg

Robert Zebahl
102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3/5
STF1517 (AB): 2020-03-27: At 160x the double star immediately appears elongated, but without any noticeable notching or difference in brightness. At 224x not really better. Observation at moderate seeing (3/5).
152mm f/5.9, 225x, Bortle 7, SQM-L 18.8, Seeing 3/5
STF1517 (AB): 2020-03-27: Clearly elongated. In some moments the double star appeared notched with a small difference in brightness. Observation at moderate seeing (3/5).

STF 1521 (**)

Name: STF1521
Type: **
Constellation: Leo
Coordinates: 11h15m20.95s / +27°34'15.60"

Components:
m1 m2 ρ θ Year
7m7 8m1 3.8" 97° 2019
Robert Zebahl
70mm f/5.7, 67x, Bortle 6-, NELM 5m0, SQM-L 19.1
At 44x still very close, finely separated pair with visible difference in brightness, rather faint. At 67x nicely separated, at 100x very easy. Colors were not clearly visible.

STF 1523 (**)

Name: STF1523, xi UMa, 53 UMa, Alula Australis
Type: **
Constellation: UMa
Coordinates: 11h18m10.90s / +31°31'45.00"

Components:
m1 m2 ρ θ Year
AB 4m3 4m8 2.1" 155° 2019

../images/binary-star-orbits/STF1523-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 83x, Bortle 6-, SQM-L 19.1
2019-02-09: Already seen as '8' at 83x. At 125x the overlapping of both Airy disks was visible, but also a slight difference in brightness.

../sketches/2019-02-09_xi_uma.jpg

70mm f/5.7, 100x, Bortle 6
2018-02-18: Very close together with similar brightness. At first glance seen as an '8', looking closer I partly split both components. Similar view also at 128x.

70mm f/5.7, 133x
2020-03-15: Splendid sight! Beautifully separated with almost touching diffraction disks. The rather small difference in brightness was well visible. The diffraction rings of both components coalesced.

102mm f/11, 160x
2020-03-16: Awesome! Bright with lovely, subtle diffraction rings. The distance between both components is a smaller than the diameter of the diffraction disk of the fainter component.

120mm f/5, 168x, Bortle 6, SQM-L 19.1
2018-02-14: Well split with slight difference in brightness.
152mm f/5.9, 129x, Bortle 6, NELM 5m0+
2019-02-06: Well split with visible difference in brightness. The colors of both components appeared equal.

STF 1537 (**)

Name: STF1537
Type: **
Constellation: Leo
Coordinates: 11h24m28.94s / +20°37'16.50"

Components:
m1 m2 ρ θ Year
8m2 9m1 2.3" 358° 2019
Robert Zebahl
102mm f/11, Bortle 7, SQM-L 18.8, Seeing 3/5
2020-03-27: At 62x almost, at 86x clearly separated, whereby the components are still very close together. The companion appears rather dim. The slight difference in brightness is already visible at 62x. At 125x the double star shows itself clearly separated. The primary component appears more white, the companion appears a bit warmer in color.

152mm f/5.9, Bortle 7, SQM-L 18.8, Seeing 3/5
2020-03-27: At 49x the double star presents itself clearly elongated, at 69x it is almost separable. The two diffraction disks are well visible. At 100x very nicely separated at still quite small separation. The primary component appears rather white, the companion shows up in a warmer hue. A moderate difference in brightness is visible.

STF 1540 (**)

Name: STF1540, 83 Leo
Type: **
Constellation: Leo
Coordinates: 11h26m45.32s / +03°00'47.20"

Components:
m1 m2 ρ θ Year
AB 6m5 7m5 28.4" 150° 2018
Robert Zebahl
55mm f/9.1, 16x, Bortle 6, SQM-L 19.5
Wonderful double with slight color contrast in a very nice field. Together with tau Leo stunning view. Slightly unequal. A appeared white-yellowish, B rather grey-bluish.

../sketches/2019-03-09_83_leo_tau_leo.jpg

STF 1547 (**)

Name: STF1547, 88 Leo
Type: **
Constellation: Leo
Coordinates: 11h31m44.94s / +14°21'52.20"

Components:
m1 m2 ρ θ Year
AB 6m3 9m1 15.5" 332° 2018

../images/binary-star-orbits/STF1547-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 42x, Bortle 6, SQM-L 19.5
Well split with moderate distance. Primary component appeared white-yellowish. Pretty unequal pair.

STF 1552 (**)

Name: STF1552, 90 Leo
Type: **
Constellation: Leo
Coordinates: 11h34m42.50s / +16°47'48.90"

Components:
m1 m2 ρ θ Year
AC 6m3 9m8 63.4" 235° 2018
AB 6m3 7m3 3.1" 209° 2018
Robert Zebahl
55mm f/9.1, 42x, Bortle 6, SQM-L 19.5
AB: A and B very tight and unequal. Much fainter component C very wide apart. All components almost in line. Very nice view.

../sketches/2019-03-09_90_leo.jpg

STF 1579 (**)

Name: STF1579, 65 UMa
Type: **
Constellation: UMa
Coordinates: 11h55m05.74s / +46°28'36.60"

Components:
m1 m2 ρ θ Year
AB-C 6m7 8m3 3.8" 40° 2017
AB-D 6m7 7m0 62.5" 114° 2018
Robert Zebahl
55mm f/9.1, 83x, Bortle 6-, SQM-L 19.1
AB-C: Easy to split, but the faint C component only appeared as a tiny star.

../sketches/2019-02-09_65_uma.jpg

55mm f/9.1, 27x, Bortle 6-, SQM-L 19.1
AB-D: Easy to separate with large distance and very small difference in brightness. The D component showed a bluish tint, the lighter one (AB) a slightly yellowish tint. At higher magnification also the faint C component is visible.

STF 1626 (**)

Name: STF1626
Type: **
Constellation: Dra
Coordinates: 12h16m47.11s / +70°08'45.70"

Components:
m1 m2 ρ θ Year
9m4 9m6 2.1" 2017
Robert Zebahl
120mm f/5, 150x, Bortle 6, NELM 5m0+, SQM-L 19.3
Components similar in brightness, pretty faint, close together, but clearly split.

STF 1657 (**)

Name: STF1657, 24 Com
Type: **
Constellation: Com
Coordinates: 12h35m07.76s / +18°22'37.40"

Components:
m1 m2 ρ θ Year
5m1 6m3 20.2" 272° 2018
Robert Zebahl
102mm f/11, 28x
Very beautiful view with moderate distance and difference in brightness. A: glossy, light orange, B: white- bluish.

8" f/6, 60x, Bortle 4, NELM 6m0, SQM-L 21.0
Well split with obvious difference in brightness. Fainter component appeared bluish, the brighter one slightly orange.

STF 1670 (**)

Name: STF1670, gamma Vir, 29 Vir, Porrima
Type: **
Constellation: Vir
Coordinates: 12h41m39.60s / -01°26'57.90"

Components:
m1 m2 ρ θ Year
AB 3m5 3m5 2.7" - 2018

../images/binary-star-orbits/STF1670-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 56x
2019-05-18: At 38x slightly elongated. At 56x touching diffraction disks. At 71x clearly separated with very small gap.

70mm f/5.7, 104x, Bortle 6, SQM-L 19.5
2019-05-04: At 47x clearly visible as '8', at 73x split with almost touching diffraction disks. At 104x clearly separated, equally bright and pretty close together. The gap was smaller than the diameter of the diffraction disk.
102mm f/11, 125x
2019-05-01: Extremely nice double star! Equally bright and relatively close together. Both components appeared yellowish-white.

STF 1692 (**)

Name: STF1692, 12 CVn, alpha CVn, Cor Caroli
Type: **
Constellation: CVn
Coordinates: 12h56m01.67s / +38°19'06.20"

Components:
m1 m2 ρ θ Year
AB 2m9 5m5 19.5" 230° 2018
Robert Zebahl
70mm f/5.7, 22x
Beautiful view. Clearly unequal with nice angular distance. Primary component appeared in pale yellow, secondary component silvery-white.

4.5" f/8, 28x, Bortle 6, NELM 5m3, SQM-L 19.7
Well split with big difference in brightness.

STF 1694 (**)

Name: STF1694
Type: **
Constellation: Cam
Coordinates: 12h49m13.80s / +83°24'46.30"

Components:
m1 m2 ρ θ Year
AB 5m3 5m7 21.8" 324° 2017
Robert Zebahl
70mm f/5.7, 15x, Bortle 6-, NELM 5m0, SQM-L 19.1
Easy to split with noticeable angular distance and slight difference in brightness. The faint component tends to be more bluish, the brighter one appeared more light yellowish.

STF 1695 (**)

Name: STF1695
Type: **
Constellation: UMa
Coordinates: 12h56m17.64s / +54°05'58.10"

Components:
m1 m2 ρ θ Year
AB 6m0 7m8 3.9" 281° 2017
AC 6m0 12m3 131.7" 139° 2015
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
AB: Easily separable, but still quite close together with a relatively large difference in brightness. The companion appeared only as a tiny star.

STF 1724 (**)

Name: STF1724, theta Vir, 51 Vir
Type: **
Constellation: Vir
Coordinates: 13h09m57.01s / -05°32'20.10"

Components:
m1 m2 ρ θ Year
AB 4m4 9m4 6.8" 342° 2014
Robert Zebahl
70mm f/5.7, 47x, Bortle 6, SQM-L 19.5
Easy to split with large difference in brightness. Very faint B component clearly apart from the primary component.

STF 1734 (**)

Name: STF1734
Type: **
Constellation: Vir
Coordinates: 13h20m41.57s / +02°56'31.90"

Components:
m1 m2 ρ θ Year
6m8 7m3 1.1" 173° 2017

../images/binary-star-orbits/STF1734-orbit.jpg

Robert Zebahl
70mm f/5.7, 104x, Bortle 6, SQM-L 19.5
Double star appeared slightly elongated without noticeable notching.

STF 1740 (**)

Name: STF1740
Type: **
Constellation: Vir
Coordinates: 13h23m39.16s / +02°43'24.00"

Components:
m1 m2 ρ θ Year
7m1 7m4 25.6" 75° 2018
Robert Zebahl
70mm f/5.7, 33x, Bortle 6, SQM-L 19.5
Easy to separate, slightly unequal with moderate angular distance. A: pale orange, B: color not clearly perceptible.

STF 1755 (**)

Name: STF1755
Type: **
Constellation: CVn
Coordinates: 13h32m21.99s / +36°49'05.60"

Components:
m1 m2 ρ θ Year
7m3 8m1 4.1" 133° 2018
Robert Zebahl
70mm f/5.7, 67x, Bortle 6-, NELM 5m0, SQM-L 19.1
At 31x just separable, extremely tight. At 44x clearly separated, but still close, relatively dim pair with moderate difference in brightness. At 67x and 100x well separable. The primary component appeared slightly orange.

STF 1788 (**)

Name: STF1788
Type: **
Constellation: Vir
Coordinates: 13h54m58.20s / -08°03'31.90"

Components:
m1 m2 ρ θ Year
AB 6m7 7m3 3.7" 101° 2018

../images/binary-star-orbits/STF1788-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 47x, Bortle 6, SQM-L 19.5
Very nice view! Pretty tight together with a moderate difference in brightness.

STF 1834 (**)

Name: STF1834
Type: **
Constellation: Boo
Coordinates: 14h20m17.60s / +48°30'25.10"

Components:
m1 m2 ρ θ Year
8m1 8m3 1.6" 104° 2018

../images/binary-star-orbits/STF1834-orbit.jpg

Robert Zebahl
120mm f/5, 150x, Bortle 6, NELM 5m0+, SQM-L 19.4
At 108x elongated, at 150x barely split with similarly bright components.

STF 1835 & BU1111 (**)

Name: STF1835 & BU1111, WDS14234+0827
Type: **
Constellation: Boo
Coordinates: 14h23m22.74s / +08°26'47.90"

Components:
m1 m2 ρ θ Year
STF1835 A-BC 5m0 6m8 6.2" 196° 2018
BU1111 BC 7m4 7m7 0.3" 16° 2018

../images/binary-star-orbits/BU1111-BC-orbit.jpg

Robert Zebahl
102mm f/11, 62x
STF1835 (A-BC): At 28x barely split with visible difference in brightness. At 62x easy to separate. The colors seemed similar.

STF 1877 (**)

Name: STF1877, epsilon Boo, Izar
Type: **
Constellation: Boo
Coordinates: 14h44m59.14s / +27°04'29.90"

Components:
m1 m2 ρ θ Year
AB 2m6 4m8 2.8" 347° 2018
Robert Zebahl
55mm f/9.1, 125x
The fainter component was seen as permanent brightening on the first diffraction ring of the primary component.

60mm f/10, 192x, Bortle 6-, SQM-L 19.1
Easy to split, whereby the much fainter component lies on the first diffraction ring of the primary component. The primary component itself appeared slightly yellowish.

../sketches/2018-04-10_epsilon_boo.jpg

70mm f/5.7, 133x, Bortle 6, SQM-L 19.2
Easy to split, very unequal. A appeared in pale orange, B was visible as a very tiny, grey star on the first diffraction ring of component A.

120mm f/5, 192x, Bortle 4, SQM-L 21.3
At 85x the fainter component was easily visible but not separated. At 192x well split. The fainter component was almost on the first diffraction ring of the primary component. Quite big difference in brightness. I did not looked at the color of the components.

STF 1884 (**)

Name: STF1884
Type: **
Constellation: Boo
Coordinates: 14h48m23.37s / +24°22'01.00"

Components:
m1 m2 ρ θ Year
6m6 7m5 2.1" 58° 2019

../images/binary-star-orbits/STF1884-orbit.jpg

Robert Zebahl
102mm f/11, 86x
At 86x pretty tight and unequal. At 160x clearly split. A: white, B: slightly orange.

STF 1886 (**)

Name: STF1886
Type: **
Constellation: Boo
Coordinates: 14h51m02.31s / +09°43'25.20"

Components:
m1 m2 ρ θ Year
AB 7m6 9m7 7.9" 224° 2018
Robert Zebahl
102mm f/11, 28x
At 28x, the B component appeared rather faint and pretty close to the primary component. At 62x both components were clearly visible and unequal. A: slightly orange, B: greyish.

STF 1890 (**)

Name: STF1890, 39 Boo
Type: **
Constellation: Boo
Coordinates: 14h49m41.37s / +48°43'15.60"

Components:
m1 m2 ρ θ Year
6m3 6m7 2.5" 46° 2019

../images/binary-star-orbits/STF1890-orbit.jpg

Robert Zebahl
70mm f/5.7, 67x, Bortle 6, SQM-L 19.2
At 44x elongated, partly notched. At 67x split, but very tight. A difference in brightness was not seen. At 133x clearly separated with little difference in brightness. A appeared pale yellow, B rather warm-white.

STF 1954 (**)

Name: STF1954, delta Ser, 13 Ser
Type: **
Constellation: Ser
Coordinates: 15h34m48.14s / +10°32'20.00"

Components:
m1 m2 ρ θ Year
AB 4m2 5m2 4.0" 171° 2019
AC 4m2 13m9 66.6" 18° 2014
CD 13m9 14m6 4.0" 341° 2018

../images/binary-star-orbits/STF1954-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 4, SQM-L 20.9
AB: Easy to separate with relatively close components and a clear difference in brightness. A appeared rather white, B slightly orange.

STF 1964 & HU1167 (**)

Name: STF1964 & HU1167, WDS15382+3615
Type: **
Constellation: CrB
Coordinates: 15h38m12.91s / +36°14'48.60"

Components:
m1 m2 ρ θ Year
HU1167 AB 8m1 9m9 1.4" 80° 2016
STF1964 AC 8m1 8m1 14.5" 90° 2017
STF1964 AD 8m1 9m0 15.1" 84° 2018
STF1964 CD 8m1 9m0 1.5" 21° 2019

../images/binary-star-orbits/HU1167-AB-orbit.jpg ../images/binary-star-orbits/STF1964-CD-orbit.jpg

Robert Zebahl
102mm f/11, 62x
STF1964 (AC): Rather wide pair, equal without visible difference in color.
120mm f/5, 23x, Bortle 6, NELM 5m0+, SQM-L 19.4
STF1964 (AC): Nice double star, well split with equally bright components.

STF 1965 (**)

Name: STF1965, zeta 2 CrB
Type: **
Constellation: CrB
Coordinates: 15h39m22.68s / +36°38'09.00"

Components:
m1 m2 ρ θ Year
5m0 5m9 6.3" 306° 2019
Robert Zebahl
102mm f/11, 28x
At 28x very tight and barely split, unequal. At 86x very nice view. No difference in color: both components appeared white.

120mm f/5, 48x, Bortle 6, NELM 5m0+, SQM-L 19.4
Very nice double star, well split with noticeable difference in brightness.

STF 1973 (**)

Name: STF1973
Type: **
Constellation: CrB
Coordinates: 15h46m24.50s / +36°26'45.60"

Components:
m1 m2 ρ θ Year
7m6 8m8 30.8" 320° 2015
Robert Zebahl
120mm f/5, 23x, Bortle 6, NELM 5m0+, SQM-L 19.4
Nice double star, easy to split with noticeable difference in brightness.

STF 2016 (**)

Name: STF2016
Type: **
Constellation: Her
Coordinates: 16h12m07.05s / +11°54'39.20"

Components:
m1 m2 ρ θ Year
8m5 9m6 7.5" 147° 2019
Only 11 arcminutes northwestward is the pretty bright planetary nebula IC4593.

Robert Zebahl
120mm f/5, 40x, Bortle 4, SQM-L 21.0
Conditions in the target region: SQM-L 20.6
Split at 40x with obvious difference in brightness. At 75x easily split.

STF 2021 (**)

Name: STF2021, 49 Ser
Type: **
Constellation: Her
Coordinates: 16h13m18.45s / +13°31'37.20"

Components:
m1 m2 ρ θ Year
AB 7m4 7m5 4.0" 358° 2019

../images/binary-star-orbits/STF2021-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 4, SQM-L 20.9
Lovely split. Almost equal pair with relatively close components.

STF 2034 (**)

Name: STF2034
Type: **
Constellation: UMi
Coordinates: 15h48m43.02s / +83°37'10.50"

Components:
m1 m2 ρ θ Year
7m7 8m0 1.1" 110° 2017
Robert Zebahl
102mm f/11, 187x, Bortle 6-, SQM-L 18.8
At 187x clearly elongated, partly visible as '8' with slight difference in brightness. At 280x two distinct, slightly overlapping Airy disks visible.

STF 2054 (**)

Name: STF2054
Type: **
Constellation: Dra
Coordinates: 16h23m47.19s / +61°41'47.00"

Components:
m1 m2 ρ θ Year
AB 6m2 7m1 1.0" 350° 2018
Robert Zebahl
70mm f/5.7, 133x, Bortle 4, SQM-L 20.9
Not split in any way.

102mm f/11, 160x, Bortle 6, SQM-L 19.4
Immediately visible as a double star. The diffraction disks overlapped slightly. The difference in brightness was clearly visible. Together with the nearby double star eta Dra in the same field of view, the sight was highly fascinating, as both double stars are very different in their appearance.

../sketches/2019-06-25_stf2054.jpg

STF 2084 (**)

Name: STF2084, zeta Her, 40 Her
Type: **
Constellation: Her
Coordinates: 16h41m17.16s / +31°36'09.80"

Components:
m1 m2 ρ θ Year
3m0 5m4 1.6" 115° 2018

../images/binary-star-orbits/STF2084-orbit.jpg

Robert Zebahl
102mm f/11, 280x, Bortle 6, SQM-L 19.4
After a longer, concentrated observation, a permanent brightening of the first diffraction ring of the primary component could be seen at the correct position angle. The brightening appeared only arch-shaped without any noticeable condensation.

../sketches/2019-06-25_zeta_her.jpg

102mm f/11, 224x
Faint companion as distinct brightening on the first diffraction ring visible. In steadier moments visible as small, round condensation.

../sketches/2019-06-30_zeta_her.jpg

STF 2098 (**)

Name: STF2098
Type: **
Constellation: Her
Coordinates: 16h45m43.47s / +30°00'17.20"

Components:
m1 m2 ρ θ Year
AB 8m8 9m6 14.3" 145° 2015
AC 8m8 8m8 65.9" 128° 2015
AD 8m8 11m0 67.6" 18° 2015
DE 11m0 13m7 5.8" 268° 2015
Robert Zebahl
102mm f/11, 86x, Bortle 6
Already at 28x the components A, B and C were noticeable at first view. At 86x, component D could also be observed very well. The components are all comparatively far apart.

../sketches/2019-06-23_stf2098.jpg

STF 2140 (**)

Name: STF2140, alpha Her, 64 Her, Ras Algethi
Type: **
Constellation: Her
Coordinates: 17h14m38.86s / +14°23'24.90"

Components:
m1 m2 ρ θ Year
AB 3m5 5m4 4.8" 105° 2018

../images/binary-star-orbits/STF2140-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 41x
Well split with noticeable difference in brightness.
120mm f/5, 100x, Bortle 6
Easily split with noticeable difference in brightness. A: intensively orange colored, B: slightly orange.

STF 2161 (**)

Name: STF2161, 75 Her, rho Her
Type: **
Constellation: Her
Coordinates: 17h23m40.97s / +37°08'45.30"

Components:
m1 m2 ρ θ Year
AB 4m5 5m4 4.1" 321° 2018
Robert Zebahl
55mm f/9.1, 38x
Very nice view. Easily split with visible difference in brightness. Pretty tight. Component A appeared rather white, B slightly yellowish. The double star forms with two other, fainter field stars a conspicuous, acute-angled triangle, whereby the double star marks the tip.

STF 2224 (**)

Name: STF2224, V826 Her
Type: **
Constellation: Her
Coordinates: 17h45m58.44s / +39°19'21.00"

Components:
m1 m2 ρ θ Year
AB 6m7 10m0 7.9" 349° 2015
Robert Zebahl
120mm f/5, 100x, Bortle 6
Well split, rather close and obviously unequal. Primary component appeared slightly yellowish, secondary still visible with direct vision.

STF 2280 (**)

Name: STF2280, 100 Her
Type: **
Constellation: Her
Coordinates: 18h07m49.56s / +26°06'04.40"

Components:
m1 m2 ρ θ Year
AB 5m8 5m8 14.3" 183° 2018
Robert Zebahl
120mm f/5, 40x, Bortle 5+, SQM-L 20.8
Conditions in the target region: SQM-L 20.5
Very nice, evident double star with equally bright components.

152mm f/5.9, 22x, Bortle 3-, SQM-L 21.3
Beautiful view. Easy to separate with components of the same brightness. It is noticeable that there are no brighter stars in the immediate vicinity, so that the double star stands out very well.

STF 2308 (**)

Name: STF2308
Type: **
Constellation: Dra
Coordinates: 18h00m09.07s / +80°00'13.70"

Components:
m1 m2 ρ θ Year
40/41 Dra AB 5m7 6m0 18.7" 232° 2018
AC 5m7 8m3 224.7" 129° 2015

../images/binary-star-orbits/STF2308-AB-orbit.jpg

Robert Zebahl
102mm f/11, 28x
Very nice, slightly uneven pair. Components appeared yellowish-white. Beautiful surroundings. On the sketch the components A, B and C are visible.

../sketches/2019-06-30_40_41_dra.jpg

STF 2323 (**)

Name: STF2323, 39 Dra
Type: **
Constellation: Dra
Coordinates: 18h23m54.65s / +58°48'02.10"

Components:
m1 m2 ρ θ Year
AC 5m1 8m0 89.1" 19° 2017
AB 5m1 8m1 3.8" 348° 2018

../images/binary-star-orbits/STF2323-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 27x
AC: Pretty wide, unequal pair. Die brighter A component appeared white.
55mm f/9.1, 71x
AB: Very nice. The B component seemed to be comparable faint as the C component.

../sketches/2019-05-18_39_dra.jpg

STF 2349 (**)

Name: STF2349
Type: **
Constellation: Lyr
Coordinates: 18h36m37.34s / +33°28'08.50"

Components:
m1 m2 ρ θ Year
AB 5m4 9m4 7.2" 204° 2016
Robert Zebahl
102mm f/11, 125x, Bortle 6
Easy to split with a clear difference in brightness. The companion only appeared as a tiny star.

../sketches/2019-06-23_stf2349.jpg

STF 2351 (**)

Name: STF2351
Type: **
Constellation: Lyr
Coordinates: 18h36m12.00s / +41°16'41.20"

Components:
m1 m2 ρ θ Year
7m6 7m6 5.0" 160° 2019
Robert Zebahl
70mm f/5.7, 57x
Beautiful, little double star with equally bright components at a moderate distance.

STF 2404 (**)

Name: STF2404
Type: **
Constellation: Aql
Coordinates: 18h50m45.55s / +10°58'35.20"

Components:
m1 m2 ρ θ Year
6m9 7m8 3.7" 181° 2019
Robert Zebahl
70mm f/5.7, 44x
Already at 22x the double star is striking due to its orange color. At 44x split, but rather tight with a clear difference in brightness. At 100x the primary component appears in a bright orange, the secondary component shows a bluish tint.

STF 2434 (**)

Name: STF2434
Type: **
Constellation: Aql
Coordinates: 19h02m44.38s / -00°42'40.40"

Components:
m1 m2 ρ θ Year
A-BC 8m4 8m9 27.8" 88° 2019
Robert Zebahl
120mm f/5, 18x, Bortle 4, SQM-L 21.1
Easily split with similar brightness.

STF 2449 (**)

Name: STF2449
Type: **
Constellation: Aql
Coordinates: 19h06m23.04s / +07°09'20.10"

Components:
m1 m2 ρ θ Year
7m2 7m7 8.0" 289° 2015
Robert Zebahl
70mm f/5.7, 22x
At 22x well separable, but quite close together. Some fainter and similarly bright stars in the immediate surrounding. At 57x small difference in brightness. Main component looked white-bluish, companion slightly orange.

STF 2461 (**)

Name: STF2461, 17 Lyr
Type: **
Constellation: Lyr
Coordinates: 19h07m25.58s / +32°30'06.20"

Components:
m1 m2 ρ θ Year
AB 5m3 9m1 3.2" 281° 2017
Robert Zebahl
152mm f/5.9, 129x, Bortle 6
At 129x clearly split. The B component was just visible as pretty faint, tiny star. At 270x much easier visible.

STF 2470 (**)

Name: STF2470
Type: **
Constellation: Lyr
Coordinates: 19h08m45.20s / +34°45'37.10"

Components:
m1 m2 ρ θ Year
7m0 8m4 13.8" 267° 2017
Robert Zebahl
102mm f/11, 40x, Bortle 6, SQM-L 19.4
Striking, especially with STF 2474 in one visual field. The color of the components was not clearly visible. Worthwhile! Sketch see STF 2474.

STF 2474 (**)

Name: STF2474
Type: **
Constellation: Lyr
Coordinates: 19h09m04.35s / +34°35'59.90"

Components:
m1 m2 ρ θ Year
AB 6m8 7m9 15.9" 264° 2018
Robert Zebahl
102mm f/11, 40x, Bortle 6, SQM-L 19.4
Pretty conspicuous, easy double star. Especially attractive with the nearby double star STF 2470, as both are very similar in brightness, distance and position angle. The color of both components appeared slightly yellowish-orange.

../sketches/2019-06-26_stf2470_stf2474.jpg

STF 2486 (**)

Name: STF2486
Type: **
Constellation: Cyg
Coordinates: 19h12m05.03s / +49°51'20.70"

Components:
m1 m2 ρ θ Year
AB 6m5 6m7 7.1" 204° 2019

../images/binary-star-orbits/STF2486-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 22x, Bortle 6-
At 22x barely split with a slight difference in brightness. At 44x the primary looked orange. I could not determine the color of the companion.

STF 2496 (**)

Name: STF2496
Type: **
Constellation: Cyg
Coordinates: 19h15m19.18s / +50°04'16.00"

Components:
m1 m2 ρ θ Year
AB 6m5 10m0 2.1" 81° 2015
AC 6m5 11m2 186.1" 242° 2003
Robert Zebahl
152mm f/5.9, 270x, Bortle 6
AB: In steadier moments, the much fainter companion can be seen near the first diffraction ring of the primary component.

STF 2578 (**)

Name: STF2578
Type: **
Constellation: Cyg
Coordinates: 19h45m39.65s / +36°05'27.60"

Components:
m1 m2 ρ θ Year
AB 6m4 7m0 14.9" 125° 2018
Robert Zebahl
70mm f/5.7, 22x
At 22x easy with visible brightness and color difference. The slight color difference is even better visible at 44x: A appears white-yellowish, B slightly bluish.

STF 2579 (**)

Name: STF2579, delta Cyg, 18 Cyg
Type: **
Constellation: Cyg
Coordinates: 19h44m58.44s / +45°07'50.50"

Components:
m1 m2 ρ θ Year
AB 2m9 6m3 2.8" 218° 2016

../images/binary-star-orbits/STF2579-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 200x, Bortle 6-
At 100x only indicated. At 200x the much fainter companion is visible as a slightly elongated brightening on the first diffraction ring.

STF 2583 (**)

Name: STF2583, pi Aql
Type: **
Constellation: Aql
Coordinates: 19h48m42.05s / +11°48'57.30"

Components:
m1 m2 ρ θ Year
AB 6m3 6m8 1.4" 106° 2018
Robert Zebahl
120mm f/5, 337x, Bortle 4-, SQM-L 20.7
At 100x elongated, at 200x seen as '8'. At 337x split in moments of good seeing, but still very tight. Overall the seeing was not so good.

STF 2605 (**)

Name: STF2605, psi Cyg, 24 Cyg
Type: **
Constellation: Cyg
Coordinates: 19h55m37.82s / +52°26'20.50"

Components:
m1 m2 ρ θ Year
AB 5m0 7m5 2.8" 177° 2014
Robert Zebahl
70mm f/5.7, 100x, Bortle 6-
At 80x difficult. At 100x and 133x the fainter component was clearly visible as small, roundish, partly slightly oval brightening.

STF 2644 (**)

Name: STF2644
Type: **
Constellation: Aql
Coordinates: 20h12m35.09s / +00°52'00.20"

Components:
m1 m2 ρ θ Year
6m9 7m1 2.6" 206° 2018
Robert Zebahl
70mm f/5.7, 57x
Very tight at 57x, but separable without noticeable difference in brightness. At 100x very small difference in brightness visible. The colors of both components appeared to be the same, but not clearly perceptible.

STF 2671 (**)

Name: STF2671
Type: **
Constellation: Cyg
Coordinates: 20h18m24.76s / +55°23'49.80"

Components:
m1 m2 ρ θ Year
AB 6m0 7m5 3.8" 337° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
Pretty tight with a clear difference in brightness. I couldn't see anything conspicuous regarding colors.

STF 2675 (**)

Name: STF2675, kappa Cep, 1 Cep
Type: **
Constellation: Cep
Coordinates: 20h08m53.32s / +77°42'40.90"

Components:
m1 m2 ρ θ Year
AB 4m4 8m3 7.3" 120° 2015
Robert Zebahl
55mm f/9.1, 38x, Bortle 6
At 27x faint companion not visible. At 38x and higher magnification the companion is quite easily visible as faint, tiny star. Very nice, uneven pair!

STF 2690 (**)

Name: STF2690
Type: **
Constellation: Del
Coordinates: 20h31m11.94s / +11°15'33.70"

Components:
m1 m2 ρ θ Year
A-BC 7m1 7m4 17.8" 255° 2019
Robert Zebahl
8" f/6, 37x, Bortle 4, NELM 5m7+, SQM-L 20.9
Conditions in the target region: NELM 5m4+, SQM-L 20.6
Evident double star with almost equally bright components and no noticeable contrast in color.

STF 2737 (**)

Name: STF2737, epsilon Equ, 1 Equ
Type: **
Constellation: Equ
Coordinates: 20h59m04.54s / +04°17'37.80"

Components:
m1 m2 ρ θ Year
AB 6m0 6m3 0.2" 281° 2018
AD 6m0 13m1 69.3" 293° 2013
AB-C 5m3 7m0 10.6" 67° 2018

../images/binary-star-orbits/STF2737-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 22x, Bortle 6-
AB-C: At 22x well seperated, but still relatively close together with a clear difference in brightness. At 44x AB looked rather white. The color of C was not apparent.

STF 2742 (**)

Name: STF2742
Type: **
Constellation: Equ
Coordinates: 21h02m12.51s / +07°10'47.30"

Components:
m1 m2 ρ θ Year
7m4 7m6 2.9" 215° 2017
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
At 44x almost split with slight difference in brightness. At 57x split, but tight.

STF 2765 (**)

Name: STF2765
Type: **
Constellation: Equ
Coordinates: 21h10m59.31s / +09°32'57.90"

Components:
m1 m2 ρ θ Year
AB 8m5 8m5 2.9" 82° 2018
AC 8m5 14m2 44.2" 167° 2015
Robert Zebahl
70mm f/5.7, 80x, Bortle 6-
AB: At 44x pretty faint, clearly elongated, notched. At 57x almost separated. At 80x and 100x clearly separated, rather tight, matched.

STF 2767 (**)

Name: STF2767
Type: **
Constellation: Peg
Coordinates: 21h10m30.43s / +19°57'35.70"

Components:
m1 m2 ρ θ Year
8m2 8m5 2.5" 29° 2016
Robert Zebahl
70mm f/5.7, 100x
Clearly split with slight difference in brightness.

STF 2786 (**)

Name: STF2786
Type: **
Constellation: Equ
Coordinates: 21h19m39.36s / +09°31'30.30"

Components:
m1 m2 ρ θ Year
7m5 8m2 2.8" 189° 2016
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
At 44x elongated, slightly notched. At 57x barely split with visible, but little difference in brightness.

STF 2789 (**)

Name: STF2789
Type: **
Constellation: Cyg
Coordinates: 21h19m58.84s / +52°58'44.10"

Components:
m1 m2 ρ θ Year
AB 7m7 7m9 6.8" 115° 2018
Robert Zebahl
70mm f/5.7, 44x, Bortle 6-
At 22x almost separated. The double star appeared strikingly orange and forms a conspicuous, nearly isosceles triangle with neighbouring stars. At 44x clearly separated, relatively close together with a small difference in brightness.

../sketches/2019-07-28_stf2789.jpg

STF 2793 (**)

Name: STF2793
Type: **
Constellation: Equ
Coordinates: 21h25m05.66s / +09°23'02.60"

Components:
m1 m2 ρ θ Year
AB-C 7m4 9m0 26.4" 241° 2014
Robert Zebahl
70mm f/5.7, 22x, Bortle 6-
At 22x easily separable with relatively large angular distance. C component much fainter. At 44x AB appeared white-yellowish, C somewhat reddish.

STF 2797 (**)

Name: STF2797, KP Peg
Type: **
Constellation: Peg
Coordinates: 21h26m41.14s / +13°41'17.80"

Components:
m1 m2 ρ θ Year
7m4 8m8 3.5" 217° 2011
Robert Zebahl
70mm f/5.7, 57x, Bortle 6, SQM-L 19.1
Split at 57x, but very tight with clear difference in brightness. At 100x well split. The faint B component was slightly outside the first diffraction ring of the primary component.

STF 2799 (**)

Name: STF2799
Type: **
Constellation: Peg
Coordinates: 21h28m52.79s / +11°05'05.20"

Components:
m1 m2 ρ θ Year
AB 7m4 7m4 1.8" 259° 2018

../images/binary-star-orbits/STF2799-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 100x
At 100x, barely, at 128x clearly split with equally bright components.

STF 2804 (**)

Name: STF2804
Type: **
Constellation: Peg
Coordinates: 21h32m58.30s / +20°42'44.50"

Components:
m1 m2 ρ θ Year
AB 7m7 8m0 3.7" 2018

../images/binary-star-orbits/STF2804-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 6, SQM-L 19.1
Clearly split, pretty close, moderately uneven. The primary components looked slightly orange. Very nice pair.

STF 2807 (**)

Name: STF2807
Type: **
Constellation: Cep
Coordinates: 21h17m33.47s / +82°31'03.70"

Components:
m1 m2 ρ θ Year
8m7 8m8 1.9" 309° 2016

../images/binary-star-orbits/STF2807-orbit.jpg

Robert Zebahl
70mm f/5.7, 128x, Bortle 5, NELM 5m7, SQM-L 20.6
Barely split without any noticeable difference in brightness.

STF 2840 (**)

Name: STF2840
Type: **
Constellation: Cep
Coordinates: 21h52m01.02s / +55°47'48.30"

Components:
m1 m2 ρ θ Year
AB 5m6 6m4 18.1" 197° 2018
Robert Zebahl
55mm f/9.1, 25x
Striking double star with clear distance and difference in brightness.

70mm f/5.7, 22x, Bortle 6-
Striking, beautiful double star with visible difference in brightness. At 44x A appeared rather yellowish, B slightly bluish, whereby the colors were difficult to detect.

STF 2841 (**)

Name: STF2841
Type: **
Constellation: Peg
Coordinates: 21h54m17.44s / +19°43'05.30"

Components:
m1 m2 ρ θ Year
A-BC 6m5 8m0 22.4" 110° 2018
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
At 22x easy to separate with considerable difference in brightness. The primary component appeared slightly yellowish-orange, the fainter component greyish-blue. The slight color contrast was especially visible at 44x.

STF 2845 (**)

Name: STF2845
Type: **
Constellation: Cep
Coordinates: 21h52m20.95s / +63°06'04.50"

Components:
m1 m2 ρ θ Year
AB 8m1 8m2 2.0" 173° 2016
Robert Zebahl
70mm f/5.7, 128x, Bortle 4-, SQM-L 20.9
Easy to split with equally bright components.

STF 2848 (**)

Name: STF2848
Type: **
Constellation: Peg
Coordinates: 21h58m01.45s / +05°56'25.30"

Components:
m1 m2 ρ θ Year
7m2 7m7 10.9" 57° 2015
Robert Zebahl
70mm f/5.7, 22x
At 22x nicely separated, but still relatively close together with a small difference in brightness. The brighter component appeared cooler in color (white-bluish), the fainter one warmer (slightly orange). At 44x the color impression was similar.

STF 2854 (**)

Name: STF2854
Type: **
Constellation: Peg
Coordinates: 22h04m22.52s / +13°38'53.40"

Components:
m1 m2 ρ θ Year
7m8 7m9 1.5" 84° 2017
Robert Zebahl
70mm f/5.7, 133x
Observed at 133x and 160x. Clearly elongated, from time to time with very little indentation. The air could have been steadier.

STF 2861 (**)

Name: STF2861
Type: **
Constellation: Peg
Coordinates: 22h06m01.25s / +20°48'12.40"

Components:
m1 m2 ρ θ Year
8m1 8m6 7.1" 221° 2016
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
At 22x almost separable and quite faint overall. A difference in brightness was visible. At 44x easily separable with little difference in brightness and still relatively tight.

STF 2863 (**)

Name: STF2863, xi Cep, 17 Cep
Type: **
Constellation: Cep
Coordinates: 22h03m47.45s / +64°37'40.70"

Components:
m1 m2 ρ θ Year
AB 4m5 6m4 8.2" 274° 2019

../images/binary-star-orbits/STF2863-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 27x, Bortle 6
At 27x well separable, but quite close together with a clear difference in brightness. At 71x very nice view.

STF 2873 (**)

Name: STF2873
Type: **
Constellation: Cep
Coordinates: 21h58m13.53s / +82°52'10.80"

Components:
m1 m2 ρ θ Year
AB 7m0 7m5 13.8" 66° 2017

../images/binary-star-orbits/STF2873-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 25x
Easy to split with visible difference in brightness. Stands out immediately.

STF 2903 (**)

Name: STF2903
Type: **
Constellation: Cep
Coordinates: 22h21m45.20s / +66°42'22.60"

Components:
m1 m2 ρ θ Year
7m1 7m8 4.1" 97° 2017
Robert Zebahl
55mm f/9.1, 55x
At 55x split with noticeable difference in brightness. At 83x very well split with significantly fainter component.

STF 2947 (**)

Name: STF2947
Type: **
Constellation: Cep
Coordinates: 22h49m00.68s / +68°34'12.20"

Components:
m1 m2 ρ θ Year
AB 6m9 7m0 4.7" 56° 2018
Robert Zebahl
55mm f/9.1, 40x
At 25x elongated, at 40x split, but tight. At 55x well split, almost equally bright.

STF 2968 (**)

Name: STF2968
Type: **
Constellation: Peg
Coordinates: 23h00m42.41s / +31°04'58.70"

Components:
m1 m2 ρ θ Year
6m7 9m5 3.2" 93° 2012
Robert Zebahl
70mm f/5.7, 133x
Already at 57x the companion could be guessed in the correct position angle. At 133x it was clearly visible as a faint knot on the first diffraction ring.

STF 2971 (**)

Name: STF2971
Type: **
Constellation: Cep
Coordinates: 22h56m41.48s / +78°29'45.00"

Components:
m1 m2 ρ θ Year
8m0 8m9 5.6" 2019
Robert Zebahl
55mm f/9.1, 40x
At 25x split to some extend. At 40x well split with noticeable difference in brightness.

STF 2974 (**)

Name: STF2974
Type: **
Constellation: Peg
Coordinates: 23h05m01.12s / +33°23'08.00"

Components:
m1 m2 ρ θ Year
8m1 8m5 2.7" 168° 2019
Robert Zebahl
70mm f/5.7, 100x
At 57x separated, but pretty tight with apparently equally bright components. At 100x clearly split with slight difference in brightness.

STF 2978 (**)

Name: STF2978
Type: **
Constellation: Peg
Coordinates: 23h07m27.73s / +32°49'31.30"

Components:
m1 m2 ρ θ Year
6m3 7m5 8.3" 145° 2018
Robert Zebahl
70mm f/5.7, 22x
Well separated at 22x, but relatively close together with a noticeable difference in brightness. At 57x the primary component looked slightly yellowish, the companion rather grey-bluish.

STF 2990 (**)

Name: STF2990
Type: **
Constellation: Peg
Coordinates: 23h13m17.60s / +22°05'00.70"

Components:
m1 m2 ρ θ Year
AB 8m9 9m0 2.6" 56° 2018
Robert Zebahl
70mm f/5.7, 100x
Rather faint, because I observed from the sidewalk with present moon. Well split with equally bright components.

STF 3042 (**)

Name: STF3042
Type: **
Constellation: And
Coordinates: 23h51m52.40s / +37°53'28.40"

Components:
m1 m2 ρ θ Year
7m6 7m8 5.8" 87° 2017
Robert Zebahl
55mm f/9.1, 25x, Bortle 7, SQM-L 19.0
Split, tight, nearly equally bright.

STF 3044 (**)

Name: STF3044
Type: **
Constellation: Peg
Coordinates: 23h52m59.94s / +11°55'27.40"

Components:
m1 m2 ρ θ Year
7m3 7m9 18.7" 283° 2017
Robert Zebahl
70mm f/5.7, 22x
At 22x easy to separate with small difference in brightness. A color difference was noticeable. One component looked white-bluish, the other slightly orange. However, the colors changed again and again between the components. Even at 44x the color impression remained the same.

STF 3049 (**)

Name: STF3049, sigma Cas, 8 Cas
Type: **
Constellation: Cas
Coordinates: 23h59m00.53s / +55°45'17.80"

Components:
m1 m2 ρ θ Year
AB 5m0 7m2 3.1" 326° 2017
AC 5m0 10m4 106.0" 66° 2014
Robert Zebahl
70mm f/5.7, 120x, Bortle 6-
AB: At 57x barely separated, where the B component appears as a faint tiny star. At 120x the B component is clearly visible and slightly elongated on the first diffraction ring of the primary component. Very fine.

../sketches/2019-08-25_sigma_cas.jpg

STF 3050 (**)

Name: STF3050
Type: **
Constellation: And
Coordinates: 23h59m29.33s / +33°43'26.90"

Components:
m1 m2 ρ θ Year
AB 6m5 6m7 2.5" 342° 2018

../images/binary-star-orbits/STF3050-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 83x, Bortle 6, NELM 5m0+, SQM-L 19.1
At 83x seen as '8'. From 100x to 166x seen as '8', temporarily visible with space between.
70mm f/5.7, 100x
Wonderful double star. Easy to split with slight difference in brightness.

STF 3053 (**)

Name: STF3053
Type: **
Constellation: Cas
Coordinates: 00h02m36.08s / +66°05'56.30"

Components:
m1 m2 ρ θ Year
AB 6m0 7m2 15.0" 70° 2018
Robert Zebahl
63mm f/13.3, 46x
Easy to split with noticeable difference in brightness. Brighter component appeared slightly orange, fainter one bluish.

STF 3061 (**)

Name: STF3061
Type: **
Constellation: Peg
Coordinates: 00h05m44.45s / +17°50'25.00"

Components:
m1 m2 ρ θ Year
8m4 8m5 7.8" 149° 2016
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.1
At 22x tiny pair with similarly bright, close components. Easy to separate at 44x. A small color difference was visible: The brighter component appeared somewhat warmer with a hint of orange, the fainter one slightly bluish.

STF 3062 (**)

Name: STF3062, V640 Cas
Type: **
Constellation: Cas
Coordinates: 00h06m15.81s / +58°26'12.50"

Components:
m1 m2 ρ θ Year
6m4 7m3 1.5" 2018

../images/binary-star-orbits/STF3062-orbit.jpg

Robert Zebahl
152mm f/5.9, 129x
Nice view, clearly split, but tight with visible difference in brightness.

STF 3127 (**)

Name: STF3127, delta Her, 65 Her
Type: **
Constellation: Her
Coordinates: 17h15m01.92s / +24°50'22.50"

Components:
m1 m2 ρ